What Should We Make Of Ricky Tiedemann’s Arizona Fall League Campaign?


Image credit: (Photo by Norm Hall/MLB Photos via Getty Images)

The 2023 season didn’t play out the way Ricky Tiedemann had planned. 

The Toronto Blue Jays prospect entered the season riding the high of a breakout 2022 season where he climbed three levels of the minors and produced eye-popping strikeout totals. Tiedemann was expected to blow through the competition at Double-A and Triple-A and rise to the majors by the summer of 2023. 

The thing about expectations is they rarely go according to plan for pitching prospects.

A shoulder strain in spring training delayed the start of Tiedemann’s season. He made four starts with Double-A New Hampshire, then exited a start on May 4 early with a biceps strain. 

Something was amiss even in his previous start on April 25. Tiedemann’s fastball velocity dipped to 91-92 mph in the third inning, which is out of the ordinary. He seemingly lost command of his fastball and slider altogether in that inning. The game took place on a cold and raw New England night, but Tiedemann seemed off. He was not his usual dominant self, and not the same player that had struck out 15 batters to two walks over his first two starts of the season. 

Tiedemman’s subsequent exit from his following start due to injury sent the lefthander on a tumultuous journey through the remainder of the 2023 season. 

He missed nearly three months of action. Tiedemann’s stuff returned immediately after being activated on July 29. He stormed through a two-start rehab assignment in Dunedin and returned to Double-A New Hampshire on Aug. 11. The Blue Jays were conservative with Tiedemann’s pitch limit throughout his return, limiting him initially to 50 to 60 pitches. While Tiedemann’s results were up and down early, he rounded into form late. That built some momentum heading into the Arizona Fall League.

In three of his four starts in the Arizona Fall League, Tiedemann did something he had not done since July 1, 2022 – he exceeded 70 pitches in a start while going five or more innings. He led the league in strikeouts at the time of his departure on Oct. 22. 

The fall campaign allowed Tiedemann to end on a high note. His ability to pitch deeper into games hints at full health heading into the offseason. 

As one of the top pitching prospects in baseball, Tiedemann’s fall season was naturally a point of intrigue and discussion in some corners of the internet. Chris Welsh of Prospect One Podcast recently observed Tiedemman’s release height on his slider is different relative to his fastball. 

There’s some truth to the observation. Tiedemman’s release height on his slider is lower than his fastball. As you can see below, there’s a two and a half inch difference in release height and a quarter of an inch difference in side height. 

2023Ricky TiedemannFour-Seam5.652.75
2023Ricky TiedemannSlider5.43

This leads to a few obvious questions: how unique is this for a young pitcher and does it impact results at the next level?

It’s not particularly unusual for a pitcher to drop down when delivering their slider. Eury Perez and Bryce Miller are two prominent examples of pitching prospects who made the jump to the majors this season with a similar variance in height and side on release. Both Perez and Miller’s sliders graded out as positive pitches per Fangraphs pitch values. 

PlayerPitch TypeHeightSide
Eury PerezFour-Seam6.1-2
Eury PerezSlider5.9-2.3
Release diff0.20.3
Bryce MillerFour-Seam5.8-0.7
Bryce MillerSlider5.5-1
Release diff0.30.3
Ricky TiedemannFour-Seam5.652.75
Ricky TiedemannSlider5.43
Release diff0.25-0.25

But that doesn’t necessarily explain why Tiedemann’s release numbers had a greater differential. Could it be due to his battles with health this season? 

To understand that, we have to first examine his 2022 data to see if there is a change in release. 

As you can see below, there’s always been a fairly measurable difference in the release height of both Tiedemann’s three pitches, and he’s actually tightened the release of his arsenal this season. 

2023Ricky TiedemannFour-Seam5.652.75
2023Ricky TiedemannSlider5.43
2022Ricky TiedemannFour-Seam5.82.7
2022Ricky TiedemannSlider5.43.2

The slider was Tiedemman’s most effective pitch throughout 2023 and, in particular, during the Arizona Fall League. The pitch had the highest whiff rate of any pitch in his arsenal, while also boasting the highest chase rate and a nearly equal swing rate to his fastball. 

If we’re to believe that hitters tell you the quality of a pitch with their results, the hitters are telling us Tiedemann’s slider is fooling them as much as any pitch in his arsenal. 

Now that we’ve covered the slider, the changeup release height may actually be the real concern. The difference in Tiedemann’s fastball and changeup release is significant. 

2023Ricky TiedemannFour-Seam5.652.75
2023Ricky TiedemannChangeup5.23
2022Ricky TiedemannFour-Seam5.82.7
2022Ricky TiedemannChangeup5.33.1

There’s a four and a half inches of drop between his fastball and changeup and a quarter of an inch drop in side height. Again, though, this isn’t a new issue for Tiedemann. His release point actually tightened up in 2023. 

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. 

All of this is something to watch. But it’s probably not a reason to panic.

Download our app

Read the newest magazine issue right on your phone