A deep dive into how Ricky Tiedemann and Nate Pearson compare as prospects

Ricky Tiedemann is the consensus top ranked prospect in the Toronto Blue Jays farm system and one of the top pitching prospects in baseball. Coming off a successful 2023 Arizona Fall League campaign where he won AFL Pitcher of the Year, the hype for the 21-year-old left-hander is at an all time high.

A look at Nate Pearson's journey

The last pitching prospect in the Blue Jays' farm system with this much excitement around them was Nate Pearson. It's no mystery to Jays fans that Pearson has not lived up to prospect hype up to this point. His major league career has been a struggle as he has only pitched 75.2 major league innings over the course of 3 years and has a career 5.00 ERA. Skeptics are likely wondering why Tiedemann will be any different from Pearson. All pitching prospects come with considerable risk but it would be a logical fallacy to assume that because Pearson did not pan out that Tiedemann will not either. This article aims to set the record straight about why Pearson has struggled and how Tiedemann compares and contrasts as a pitching prospect.

Pearson was drafted in June of 2017 but it was not until 2019 that he stayed healthy and truly broke out. In 2019, he pitched 101.2 innings with a 2.30 ERA across three levels. He had his workload managed that year and alternated between pitching 5 innings and 2 innings at Double-A, but by the end of the year he was regularly throwing 90+ pitches. By the start of 2020, Pearson was ranked as the 8th-best prospect in all of baseball according to MLB Pipeline. They showered him with praise in his scouting report, giving him a noteworthy 80-grade Fastball on the 20-80 scouting scale and an overall 65 Future Value (FV) grade. At the height of his prospect hype train, Pearson was billed as a top of the rotation force who had the arsenal of an ace.

Pearson's explosive fastball usually sits in the 98-101 mph range as a starter. His upper-80s slider, much like his heater, is the best in Toronto's system and highly effective against hitters on both sides of the plate thanks to its late, glove-side action. Pearson's changeup was his most improved pitch in 2019 and now projects as at least above-average, and he understands how to steal early strikes and keep hitters off-balance with his top-to-bottom curveball.

Pearson debuted in the COVID-shortened 2020 season. He made just 4 starts before hitting the injured list with a flexor strain in his right elbow. He was known for touching 100 MPH+ regularly with his fastball in the minors but it noticeably only averaged 96.1 MPH in his MLB debut, touching 98.7 MPH at its peak. He returned later that year and in two appearances as a reliever he averaged 99 MPH and 97.9 MPH on his fastball, respectively. This could have been evidence of a more healthy elbow or it could have been a typical velocity bump for a reliever. Unfortunately, the injuries did not stop there for Pearson.

It'd be easy to say that Pearson's career has been ruined by injuries. While it's usually agreed upon that injuries are mostly unpredictable, there is some merit in discussing how scouts try to predict durability with respect to pitchers. One of the biggest contributors to arm injury risk is velocity, the harder you throw the more strain you put on your arm. This is an obvious link for Pearson as he has thrown as hard as 104 MPH and has sat in the upper 90s for most of his career. Pearson does however have the pitching frame you'd look for in a hard thrower, he's a massive 6-foot-6, 255 lbs with broad shoulders and an athletic delivery. Despite this, he never fully showed he could handle a starter's workload. His velocity would often tail off into starts and Pearson's 101.2 innings pitched in 2019 are his career high by a sizeable 59 innings (including college). In fact, you could make a justifiable claim that his 2019 season in which he saw a drastic innings pitched increase may have been the root of the elbow strain he suffered in 2020.

Pearson's inability to stay healthy drifted into his pitching habits to the point where even when healthy he looked like a shell of his former self. His command and control both significantly regressed after 2019. In the scouting world, command is considered to be how well a pitcher locates their pitches in the zone and control is considered to be how well a pitcher finds the zone altogether. His 2020 elbow injury may have prompted the first signs of significant trouble with locating his pitches. He struggled greatly with repeating his delivery and in early 2021 he tried to change his mechanics to improve his health and control. This evidently did not work as he ended up needing surgery later that year on a sports hernia related to the groin injury that prompted the mechanical change. He then reverted his mechanics back.

Pearson's inconsistencies with health and mechanics made it incredibly difficult for him to ever find his prior command and control. His 2019 mark of a 2.4 BB/9 (walks per 9 innings) is still easily his career best over a meaningful sample. His command and control are the main reason why he moved to the bullpen and part of the reason he struggled this year even as he stayed healthy. Pearson did improve his walk rate in 2023 but it's still below average and he also still struggles greatly with location. He hangs his slider a lot and when he misses the top of the zone with his fastball it tends to get barreled even at it's impressive velocity. He had just a 93 Location+ this year which was 191st of 198 relievers with 40+ innings pitched.

Ricky Tiedemann's pro career is off to a promising start

Evidently, Nate Pearson's career has been a difficult one. Taking a look back at what has gone wrong gives some insight into how Ricky Tiedemann is different and also similar. The two pitchers are very different as prospects in a few obvious ways. Pearson is a right-hander who was drafted out of college as a 20-year-old and Tiedemann is a left-hander who was drafted out of junior college at 18. The difference in the age that they were drafted at is important when comparing innings pitched totals early in their career. Tiedemann was drafted in 2021 and made his pro debut in 2022. He stayed healthy all of 2022 and only paused briefly for a mid-season stint at the Blue Jays Development Complex before being promoted to Double-A. He finished the year having pitched 78.2 innings. In 2023, he dealt with shoulder soreness in Spring Training and then hit the injured list in May with left bicep inflammation. He ramped up slowly in his return but finished the year healthy for a total of 44 innings pitched and 62 innings pitched when you include the Arizona Fall League. No matter which way you count, Tiedemann's injury-riddled 2023 total would still be the second highest of Pearson's career.

Similar to Pearson, Tiedemann is a big-bodied guy with broad shoulders. He's listed at 6-foot-4 220 lbs, and is a really good athlete for his size but his delivery features some effort and is overall far less conventional than Pearson's. Tiedemann lines up on the first base side of the rubber and throws from a low slot which gives him a really tough angle for hitters. His durability is met with skepticism from scouts because of his injuries this year and him not pitching deep into games. In his first season, he typically threw 70-80 pitches and it was only after his trip to the Development Complex that he started to have his workload more closely managed. He struggled more with his health this year and the Jays were more careful with him as a result. The southpaw spent most of 2023 only throwing 3 innings per start. Towards the end of 2023 he had his pitch counts go up to the 70+ range and he completed 5 innings in three of his four AFL starts. There's some concern with how his body will hold up just like how there was with Pearson but it's notable that he already has showed more durability than Pearson did at the same age.

Comparing the arsenals

Tiedemann's overall arsenal and profile differ greatly from Pearson's. The former's fastball typically sits around 95-96 MPH and you'll see a few 93s and 94s as he gets deeper into his starts. This is excellent velocity for a left-hander but is still far off from the type of numbers that the latter was routinely hitting. Tiedemann's heater comes in at a really tough angle, especially for left-handers, and has more of a sinker shape whereas Pearson's fastball is a more conventional four-seamer. Tiedemann's fastball has a lot of horizontal run on it and has been incredible at missing barrels over his minor league career. Opposing hitters slugged just .237 against Tiedemann this year and his fastball is a big reason why. Throwing a sinker usually comes at the cost of trading whiffs for quality of contact prevention but Tiedemann's fastball gets no shortage of swings and misses all over the zone.

Tiedemann's arm slot can wander at times and he showed more difficulty locating his fastball this year than in the past. The nature of his delivery means he has a tough time locating it to the glove side but it has seemingly played as a plus pitch just about anywhere in the zone due to it's velocity, spin, slot, and shape. This is a good lesson in pitcher scouting, there's a lot more that goes into a fastball than velocity and Tiedemann has Pearson beat in a number of areas that analytically minded scouts are beginning to value more and more. It's reasonable to ask if Pearson's fastball would still get an 80 grade if it was scouted today, even with it sitting at 98 MPH it had just a 118 Stuff+ in 2023 which is very good but not even close to an 80-grade pitch.

Both Pearson and Tiedemann throw good sliders as their main secondary pitch but Tiedemann's slider is actually more of a sweeper. He trades vertical break for horizontal break and it's a wise decision considering his delivery. A sweeping slider like this comes across his body from the first base side of the rubber at a low slot and is incredibly deceiving for hitters as a result. Tiedemann changes speeds well and the gap between his fastball velocity and slider/sweeper (~13 MPH) is significantly greater than Pearson's (~10 MPH). In recent looks he has shown more of a feel for commanding his sweeper than he has with his fastball. He can throw it for called strikes but he'll also get lots of whiffs with it all over the zone. It's his favourite offering against lefties and it's not hard to see why because it will routinely look like it's about to hit them before landing for a strike.

The last pitch in Tiedemann's tool box is his changeup. It's another strong offering for him even if it often gets pushed back behind his fastball and sweeper. He likes to lean on it towards the end of his outings and has considerable feel for the pitch. His changeup gives him a standout offering against right-handed hitters and can get whiffs as well as weak contact. While hitters gear up for his dominant fastball he can swing in a changeup that hitters often swing over the top of given the vertical break separation. His strong changeup sets him apart from Pearson, who has hardly thrown one at all since 2020. A changeup is a big factor in increasing deception as well as getting weak contact and it has helped Tiedemann with tunneling and sequencing his arsenal compared to Pearson.

Tunneling is how well a pitcher blends their pitches together for hitters. It's a big factor in increasing the deception of a pitcher's arsenal and often results in a pitcher getting a lot of chases out of the zone (something that Tiedemann excels at and something that Pearson greatly struggles with). The concept of tunneling has been around forever but is still difficult to understand fully from an analytical perspective. In the case of Tiedemann, there are some differing opinions. In a FanGraphs piece covering Tiedemann and Giants prospect Kyle Harrison, Tiedemann's ability to tunnel was considered a strength.

So in addition to his pitches looking similar and then drastically diverting from their shared trajectory (as illustrated by the overlay of his full arsenal), and him messing with hitters’ timing and expectations (as shown in the at-bat against Lockridge), he’ll toy with batters by throwing his slider to the same spots as his fastball, so that the mind-fudgery is based not on a ball looking hittable until it dives out of a batter’s reach, but rather it looking unhittable until it sweeps into a guy’s reach.

Here's a GIF from that same article to illustrate the tunneling of his full arsenal.

In a recent Baseball America article (subscription required), Tiedemann's pitches having differing release heights were the subject of potential concern for his ability to deceive hitters as well at the highest level.

It remains to be seen how much of a concern this is in the long run. Perhaps Tiedemann lacks an element of tunneling. Maybe it’s nothing at all – a small change we pick up on video and in data but is less noticeable to hitters in real time.

If hitters are processing the difference, they haven’t translated it to tangible results. Any struggles for Tiedemann can just as easily be hand-waved away as issues with command location.

Tiedemann's ability to get swings and misses in and out of the zone is arguably most evident from his massive strikeout numbers. In 2022, he had 13.4 strikeouts per 9 innings (K/9) and in 2023, he had an enormous 16.8 K/9. For reference, Spencer Strider led the majors with a 13.5 K/9 this year. Despite what public perception might tell you, Pearson was never even close to this kind of a strikeout artist. In his brilliant 2019 season he had a 10.5 K/9. Pearson's career minor league K/9 is 11.5 and there's a large reliever sample in there which usually comes with a natural strikeout bump. This highlights the strength of Tiedemann's overall arsenal as a complete entity compared to Pearson, whose pitches have individual brilliance but never shined at these heights as a collective.

Another thing to consider is quality of contact. Tiedemann is a weak contact machine and his arsenal naturally does a good of keeping the ball on the ground. His ERA being as high as it was this year is largely a product of some bad luck with singles and him walking too many batters. Tiedemann has given up just 4 home runs over the course of his 122.2 total innings pitched in MiLB. Nate Pearson gave up more home runs than that in his great 2019 season alone (8).

The last comparison to consider is command and control. Unfortunately, this is an area where Tiedemann has some similar concerns to Pearson regarding injury and mechanics. As a draft prospect, the left-hander's command and control were considered to be inconsistent and he could struggle with repeating his unique delivery at times. Some of the command and control concern was alleviated in 2022 as he had a 3.3 BB/9 across the three levels he pitched at which is a good showing for someone of his age. The concerns popped up again in 2023 as Tiedemann had a 4.7 BB/9 in MiLB and a 4.0 BB/9 in his 4 starts in the fall league. It's not unusual for a pitcher to struggle with location after having multiple arm injuries in a calendar year as it can take some time for a pitcher to sync up their mechanics again. Tiedemann's command and control is definitely at the top list of my concerns with him as it is an immensely important part of being a good MLB starter. Pearson is a cautionary tale for what can happen if a pitcher continues to miss time and never finds the same consistency in their mechanics as they once had. Tiedemann's velocity and workload looked good to end the year so by all accounts he looks healthy now. The hope is that this is something that will rebound with reps and time and for most young pitchers this is the case.

However, walk rates aren’t stable over a pitcher’s career; starters generally hone their control over time, slowly lowering their walk rate as they mature, up to a certain point. Then, as their physical abilities wane, they’re forced to nibble more and take their chances at the edge of the zone, which causes their walk rate to increase again.

Hopefully this has been an insightful look into how the two pitching prospects compare. Tiedemann is looking like he'll be a big part of the story of the 2024 Blue Jays and it's important that as fans we come to understand his strengths and weaknesses individually from past players. The future is up in the air for Tiedemann but it appears to be a bright one and Jays fans are certainly due for a consistently great homegrown pitcher.