10 Aug 2025 4 min read

What's Wrong with Ryan Brasier?

From the time he came back from the injured list through his first outing against the White Sox, Ryan Brasier had established himself as a trusted middle reliever. He had a 0.49 ERA, 1.69 FIP, and 2.76 xFIP while striking out 25% of the batters he faced and walking just 3.1%. Since his second appearance in that series, however, Brasier has allowed eight runs in 3 2/3 innings, good for a 19.64 ERA, 9.92 FIP, and 6.12 xFIP. With several pitchers set to come off the injured list in the next week and limited roster flexibility, Brasier’s place in the bullpen suddenly looks like it could be in jeopardy. At first glance, though, it’s hard to see what has changed under the hood.

Advanced pitch modeling metrics like Stuff+ have their drawbacks, but they can be a useful way to identify changes in the efficacy of a pitcher’s arsenal in a small sample. You might think the veteran righty is losing velocity as the season goes on, or that his pitches have lost some bite.

Stuff+ (100 is average)

	FA	SI	FC	SL
Before	100	105	85	92
After	104	105	90	92

If anything, Brasier’s stuff has gotten better as the season has gone on, likely due to a steady increase in velocity after returning from the injured list. Stuff is only part of what makes a pitcher good, though, so we should also look to see if Brasier has stopped locating his pitches as well.

	Stuff+	Location+	Pitching+
Before	97	101	96
After	98	101	98

Nope, at least not according to the Location+ model. There is another pitch metrics model on FanGraphs, PitchingBot, which we can use to look at the same time periods:

PitchingBot (on the 20-80 scale, 50 is average)

	FA	SI	FC	SL
Before	42	60	50	41
After	47	49	46	40

	botStf	botCmd	botOvr
Before	42	54	49
After	43	63	57

PitchingBot’s command model suggests that Brasier’s command has actually improved over his recent rough stretch. To figure out what’s changed for Brasier, we’ll need to get more granular. Here’s his pitch usage and results from both sections of his season.

Before

Pitch Type	Pitch %	wOBA	xWOBA	Barrel/BBE%
FA	39.4%	.091	.307	5.3%
SL	34.3%	.230	.241	0.0%
SI	15.4%	.189	.235	0.0%
FC	11.0%	.410	.339	0.0%

After

Pitch Type	Pitch %	wOBA	xWOBA	Barrel/BBE%
FA	30.8%	.265	.315	8.3%
SL	36.8%	.342	.322	16.7%
SI	21.4%	.431	.354	6.7%
FC	11.0%	.353	.268	0.0%

Part of this difference is simply luck. Brasier allowed a .179 wOBA when his season was going well despite batted ball data indicating he should have allowed a .277 wOBA. Similarly, he’s allowed a .344 wOBA recently while his xWOBA allowed is only .324. The discrepancy between his results over this time period is bigger than that between his expected results. Even acknowledging that, he’s still getting hit much harder recently.

In his more recent stretch, Brasier has increased his slider usage and traded some of his four-seamers for sinkers. His four-seamer results were unsustainably good, but that still hasn’t been his problem. His slider has no longer been a great pitch, and his sinker, which he’s using more, has been crushed. Since Brasier’s slider has been his primary breaking ball and he’s susceptible to platoon splits, I thought maybe he was just facing more lefties than he had previously. That doesn’t seem to be the case. He has, though, allowed a wOBA .200 points higher against lefties over his recent slide than he had earlier in the season.

Against right-handed batters, Brasier mostly uses his fastball, slider, and sinker. Against lefties, he uses his sinker instead of his cutter.

Before, against righties

Pitch Type	Pitch %	wOBA	xWOBA	Barrel/BBE%
FA	36.8%	.105	.325	0.0%
SL	38.0%	.165	.215	0.0%
SI	23.9%	.189	.235	0.0%
FC	1.2%	.000	.041	0.0%

After, against righties

Pitch Type	Pitch %	wOBA	xWOBA	Barrel/BBE%
FA	25.6%	.098	.299	0.0%
SL	39.3%	.314	.274	0.0%
SI	33.3%	.431	.354	6.7%
FC	1.7%	.000	.041	0.0%

Before, against lefties

Pitch Type	Pitch %	wOBA	xWOBA	Barrel/BBE%
FA	44.0%	.074	.285	12.5%
SL	28.6%	.492	.398	0.0%
FC	27.5%	.442	.326	0.0%

After, against lefties

Pitch Type	Pitch %	wOBA	xWOBA	Barrel/BBE%
FA	40.0%	.453	.333	20.0%
SL	32.3%	.418	.448	50.0%
FC	27.7%	.442	.325	0.0%

I’ll be honest; there’s not a lot here to indicate Brasier is doing something meaningfully worse. Three things stand out:

His sinker, which he’s throwing more, is getting hit the hardest of any of his pitches to righties.
His four-seamer was getting unsustainably good results against lefties, and is now getting unsustainably bad results.
His slider hasn’t worked well against lefties all year.

Maybe the Cubs thought Brasier was getting too predictable, but I’d shift the four-seam fastball usage back up against righties instead of the sinker. For lefties, I’d probably focus more on the cutter instead of the slider, but it’s hard to say that would make a big difference.

Once we dig into individual pitch types against certain sides of the plate over specific time periods, the samples get very small. It’s hard to say where the Cubs should go from here, since nothing stands out as significantly different. I wasn’t able to find a big change in locations by looking at pitch heatmaps. I think we should expect that Brasier will bounce back from this stretch, though maybe not to his dominant form from earlier in the season. There’s always sequencing and pitch usage that can be tweaked, but the Cubs should keep using Brasier, albeit in lower leverage than before. If something changes in the pitch data, the Cubs can reevaluate, but the Ryan Brasier from earlier this year would help solidify the middle innings for a fairly average bullpen.