Five Surprising Successful Pitchers Since August: How Are They Doing It?

When examining leaderboards over a small sample (say, the last two weeks or maybe a month), you find a mixture of high-end players and surprising ones. If you are looking for late-season adds, those high-end arms aren’t likely available, but what about some of the unexpected names? We’ll look at players rostered in less than 80% in Online Championships to identify and examine pitchers in these deeper, 12-team leagues.

This isn’t intended to be a deep dive into these pitchers because we have limited time for the rest of the season. Success can occur with strong skills, luck, or a mix of both. What have they been doing? Is it sustainable? How do we feel about the upcoming matchups? We’ll examine five starting pitchers who have performed well since August to see if they can be reliable down the stretch.

Cal Quantrill, SP, Rangers

Since the start of August, Quantrill has a 1.18 ERA, 0.79 WHIP, and three wins with a 19.4% K-BB%. He has been fortunate – you can’t post that ERA and that WHIP without some good fortune – but that’s a strong K-BB%. Quantrill has been limiting hits on balls in play (.208 BABIP) and stranding runners (89.1%) over that stretch.

The Rangers started using Quantrill as a starter in late June, and we’ve seen him go deeper into games lately. He’s thrown four consecutive quality starts of 6-7 innings. Besides the luck factors, Quantrill was consolidating his arsenal among four-seamers (29.8%), splitters (26.3%), sinkers (22.5%), and cutters (13.8%) in August.

Earlier in the season, Quantrill was throwing more cutters. However, Quantrill’s cutter currently serves as his 4th or 5th offering. That’s notable because Quantrill was relying heavily on his command, with a 109 Location+ since August, similar to his 106 Location+ before August. Quantrill is commanding his four-seamer (116), sinker (110), cutter (108), and slider (110) well, with the splitter slightly above average (101) in Location+ since August.

If Quantrill maintains his K-BB% near 20% as a starting pitcher, it would be a career best and nearly double his career average of 10.1%. The larger sample for Quantrill suggests caution in expecting him to sustain the near-elite results.

Quantrill projects to face the Mariners, but he might lose his rotation spot, as Nathan Eovaldi is expected to return next week. There is an argument for Cody Bradford or Kumar Rocker to lose their starting spot, or the Rangers could use a six-man rotation down the stretch. Pitchers like Quantrill, who rely on command, can outpitch their underlying metrics, but don’t sleep on the recent strong skills and outcomes.

Zebby Matthews, SP, Twins

Matthews has a 3.50 ERA, 1.11 WHIP, and five wins in August and September. He often relied on his control, with a 35.2% ball rate throughout his career. Matthews has a 14.4% K-BB% with a .260 BABIP and 73.6% strand rate in this run, showing a mixed bag of luck and mediocre skills. For context, Matthews has been fortunate since August, compared to his career BABIP (.317) and strand rate (68.8%).

Most ERA estimators expect regression, given his 4.41 xERA and 4.01 SIERA, with his 3.84 xFIP being the most favorable if the HR/FB rate comes down. Meanwhile, the pitch mix hasn’t shifted significantly in August for Matthews, but the command has been much better. Before August, Matthews had a 95 Stuff+ and a 99 Location+, with his four-seam (100) and cutter (100) leading his arsenal from a command standpoint.

Since August, the command numbers have skyrocketed for Matthews. He has a 93 Stuff+ and a 108 Location+ since August, with five pitches at 103 or above. Matthews’s four-seamer (103), sinker (120), cutter (123), slider (111), and changeup (108) all have an above-average Location+ since the start of August.

Matthews has often lured me into him because of control and command, which can help him succeed, though we want to see more consistency. The Twins face the Tigers (at DET), Yankees (at home), and the Giants (at SF) over the next three weeks. The Tigers (89 wRC+) and Yankees (93 wRC+) have a below-average wRC+ against right-handed pitchers since August, though the Giants (109 wRC+) have been sneaky good.

It might be confirmation bias with Matthews since we’re finally seeing him command his pitches well, with luck in his favor. It appears that the Twins will use a six-man rotation to close out the season, with Joe Ryan returning this week.

Kyle Leahy, SP, Cardinals

Leahy’s ERA has been decent since the calendar turned to August (3.28), with a 1.30 WHIP and 29.1% K-BB%. Over the past two seasons, Leahy’s K-BB% hovered around 14-15%, so that 29.1% mark is definitely an outlier. However, Leahy has been capped at five innings since August, after six games with 6 or more innings before that point.

Interestingly, Leahy allowed a .415 BABIP while stranding tons of runners (78.8%) over those August and September starts. That’s notable because we often see pitchers get lucky by limiting hits and stranding runners. However, it might be due to Leahy’s groundball-heavy profile (44.7%), with a potentially higher BABIP.

Leahy uses a deep arsenal of six pitches, which he throws 13% of the time this season. That said, the only minor pitch mix change in August involves throwing slightly more changeups (18.5% in August and 20% in September), up from 14.4% in July and 14.3% in 2026. The changeup has allowed a .314 wOBA (.338 xwOBA) and elicited a 15.9% swinging-strike rate against left-handed hitters this season.

Leahy has been quite fortunate, since he doesn’t allow weak contact, given his 4.87 xERA. That said, Leahy’s 3.88 SIERA indicates we should be cautious with his skills. The Cardinals face the White Sox and Nationals in St. Louis, and the Pirates in Pittsburgh. Those look like favorable matchups, since the White Sox (97), Nationals (83), and Pirates (79) rank in the bottom half in wRC+ against right-handed pitchers since August.

Leahy fits the mold of the other starting pitchers, who rely on their command (106 Location+). However, if Leahy continues to have a limited role as a bulk opener, his win chances will decrease, making him a less-than-optimal option to stream in favorable matchups.

Hayden Wesneski, SP, Astros

Wesneski has been pitching surprisingly well this season after recovering from Tommy John surgery in May 2025. His 12% K-BB% is three points below his career average (15.2%), though he is eliciting a solid 11.4% swinging-strike rate. The sweeper has been performing well against right-handed hitters (.094 wOBA, .184 xwOBA), as usual. Interestingly, Wesneski’s sweeper generates a 15.3% swinging-strike rate against righties, meaning it might be more of a pitch for weak contact than whiffs.

Sometimes sweepers can be problematic against opposite-handed hitters, but Wesneski is leaning on them 30.4% of the time versus lefties, which leads his arsenal. The sweeper allows a .218 wOBA against lefties, though the .287 xwOBA suggests some regression. However, Wesneski’s sweeper has been eliciting more whiffs (17.4% swinging-strike rate) this season against lefties than in previous seasons.

Furthermore, Wesneski has been consistently throwing more changeups while lowering his four-seamer usage against left-handed hitters. He threw his four-seamer 41.2% (2025) and 46.7% (2024) against lefties the last two seasons, but has dialed it back to to 28.1% this season. That’s notable because Wesneski’s four-seam was typically hit hard by lefties, evidenced by a .311 wOBA (.392 xwOBA) this season. The four-seamer is also one of Wesneski’s worst pitches from a stuff standpoint (81 Stuff+).

Over the past two seasons with the Astros, Wesneski’s changeup usage has increased, with strong results. His changeup allows a .157 wOBA (.249 xwOBA) and elicits a 17.9% swinging-strike rate. It’s a small sample in 2025, but the numbers were similar, with a .139 wOBA (.119 xwOBA) and a 14.3% swinging-strike rate. The quality outcomes via the changeup stem from his command of it, with a 112 Location+ this season, up from a career average of 104.

Wesneski goes against the Phillies on Tuesday and the Rays in Tampa Bay later in the week. He likely faces Atlanta in Houston next week, with his final outing against the Athletics on the road. Those look like tough matchups because all teams have a wRC+ of 102 or higher against right-handed pitchers since August 1.

The 4.12 xFIP might be a better expectation, especially since he has been limiting home runs (5.1% HR/FB), over 10 points below his career average. Assuming Wesneski’s sweeper and changeup are effective to both sides of the plate, he could finish the season strong as a deep-league streamer.

Ryan Johnson, SP, Angels

After nine starts through July, there was only one way to go for Johnson. Before August, he posted a 7.63 ERA, 1.59 WHIP, and an 8.1% K-BB%. That came with a .293 BABIP and a 53.3% strand rate. In six starts since August 1, Johnson has been extremely fortunate. His 1.67 ERA, 1.11 WHIP are “supported” by a 2.3% K-BB%, thanks to a 98.8% LOB% and a .169 BABIP.

Johnson’s recent success reeks of regression, with a 5.22 xERA, 5.56 xFIP, and 5.72 SIERA sounding the alarm. Before August, Johnson had a 90 Stuff+ and a 94 Location+. Since August, Johnson’s stuff improved to a 98 Stuff+, but his command has taken a fall to an 82 Location+. Better stuff is great, but it’s still below average while the command falters.

From a pitch mix standpoint, Johnson has been throwing more cutters and sweepers since August. For context, Johnson threw his cutter 48.5% in August, up from 31% (July) and 27.3% (June). Similarly, Johnson’s sweeper usage jumped to 25.5% in August, increasing from July (18.5%) and June (14.6%). Those trends remained in his lone September outing. That’s notable because Johnson’s cutter (104) and sweeper (106) lead his arsenal from a Stuff+ standpoint, signaling an attempt to use his best pitches more often.

Though the splitter doesn’t grade well in Stuff+ (74), it performs well against left-handed hitters, allowing a .215 wOBA (.256 xwOBA). Furthermore, Johnson has been throwing his splitter to lefties 31.9% of the time, up from 15.6% in 2025. The splitter has an above-average movement profile with 36.7 inches of drop and 13.6 inches of arm-side movement, both moving 1.5 inches more than the average pitch. For context, his splitter is dropping three inches more, with six additional inches of arm-side movement this season, as seen in the induced movement profiles.

Unsurprisingly, Johnson’s splitter has been thrown nearly 3 mph slower with more spin (over 700 RPM) this season. That said, Johnson’s pitch mix change and splitter movement profile add more intrigue than initially anticipated based on the K-BB% and ERA estimators. Johnson projects to face the Red Sox in Boston, with the Mariners and Twins at home in Los Angeles. Then Johnson closes the season against the Mariners in Seattle. Over the past month, the Red Sox, Twins, and Mariners boast an above-average wRC+ against right-handed pitchers. Regression could hit Johnson hard in the final weeks.