Atlanta Braves fans are well-aware of the issues that Raisel Iglesias has faced in 2025 so far. After being one of the best relievers in baseball the last couple of years, Iglesias has struggled mightily to the tune of a 5.87 ERA across 16 appearances with some notable implosions along the way. There are already those that think the Braves should entertain other closing options with Daysbel Hernandez a popular name, but diagnosing Iglesias' specific problems has proven to difficult and should be at the forefront.
When looking at Iglesias' pitching profile, the tale is told loud in clear when we look at how his slider specifically has performed in 2025. Normally when a guy is struggling, the numbers just show a general regression and you have to really dig in to figure out the root cause.
In Iglesias' case, the problem is clear: his slider has performed so poorly that it seems very possible that opposing hitters know it is coming.
Raisel Iglesias' slider has been so bad that one wonders if he is tipping the pitch
It isn't often that pitch data tells such a clear story. Sometimes you will see some atypical declines in spin or velocity that can make an obvious case, but so much of pitching is command and deception with failures there requiring a bit more investigation. However, in Iglesias' case, it is abundantly clear that his slider's total lack of effectiveness is a huge problem. Here is a look at Iglesias' pitch data from this year and last just to help with understanding.
Pitch | Velocity in MPH (2025/2024) | Spin in RPM (2025/2024) | Extension in feet (2025/2024) | Batting Average against (2025/2024) |
|---|---|---|---|---|
Four-Seamer | 94.5/95.6 | 2284/2296 | 6.2/6.2 | .250/.171 |
Changeup | 89/89.5 | 1979/2044 | 6.2/6.2 | .217/.148 |
Sinker | 94.8/95.5 | 2308/2320 | 6.2/6.2 | .154/.162 |
Slider | 83.3/84.2 | 2582/2644 | 6.0/6.1 | .500/.163 |
Now, you will see a general decline in Iglesias' performance vs. last year with all of his pitches. His velocity is down a bit across the board and he isn't spinning the ball quite as well. However, opposing hitters are batting a shocking .500 against his slider in 2025 versus .163 just last season, so what gives?
Could Iglesias' slider velo being down cause some regression or even be a sign of injury/decline? Perhaps. Could the decline in spin result in more hanging sliders getting blasted into orbit against him which has certainly been a problem? Maybe. However, look at his extension (distance from the rubber to release point) numbers. He always extends a bit less on his slider, but the difference is more stark this year when compared to his other offerings.
While opposing hitters may not be able to pick up on this difference in release point themselves, this does show that Iglesias is definitely delivering his slider differently than his other pitches and hitters could have easily picked up on that in 2025. It may be the best explanation of his struggles this year other than injury and we are just going to hope that isn't the problem. Until Iglesias figures out how to throw his slider again, he either needs to abandon it or give way to someone else while he remedies the problem.