RADIO
2025 fantasy baseball pitchers draft sleepers and draft values for the later rounds. Jamie looks at pitchers who finished the season strong and are undervalued.
There aren't many things more frustrating in fantasy baseball than seeing one of your players have a big September after struggling for most of the season. Health, bad luck, and a bad situation are just some of the many reasons a player might struggle for so long only to get things together in the final month.
A big finish to 2024 might not have been enough to help your teams this year, but it isn't something that should just be discredited. Here, we're looking at pitchers who saved their biggest month of the season for September and should be targeted in 2025 drafts.
While this trio will all be taken in deeper leagues, many may ignore their September, leaving them as draft day bargains. Don't forget to follow RotoBaller on X to get notified when articles drop. The team will be bringing you all the preseason baseball stuff you need. Without further ado, let's get into this.
Featured Promo: Save 50% the regular price with discount code SPRING, for a limited time. Exclusive access to our Team Sync platform, DFS cheat sheets, Lineup Optimizers, betting/prop picks, and exclusive content from Nick Mariano and Eric Cross! GAIN ACCESS NOW
Merrill Kelly, SP, Arizona Diamondbacks
Season numbers: 73.2 IP, 5-1 W-L, 4.03 ERA, 1.17 WHIP, 63 K
September numbers: 27.2 IP, 1-1 W-L, 3.58 ERA, 0.98 WHIP, 30 K
Kelly entered the 2024 season as a top 40 starting pitcher in drafts. A reliable workhorse with a 3.33 ERA across the previous two seasons (378.0 IP). A starter on a team that had just made it to the World Series. Sure, Kelly lacked upside, but he'd be a great anchor for fantasy rotations.
And 2024 certainly started that way. After four starts (24.2 IP), Kelly had a 2-0 W-L record, 2.19 ERA, 0.93 WHIP, and 21 Ks. He was on course to comfortably outperform his ADP. Then came a shoulder issue that ultimately sidelined Kelly until mid-August. Four months of the season were lost.
When Kelly returned, he struggled. Four starts in August saw him yield 16 earned runs (21.1 IP). Kelly struck out just 12 batters while walking eight. He looked washed, for the 2024 season at least. And then came September.
By now, almost all fantasy managers had dropped Kelly meaning his September went under the radar. In five starts (27.2 IP), Kelly had a 3.58 ERA and struck out 30 batters while allowing just five walks. Nothing overly impressive but noticeable and more than just 'noise' to be ignored.
Kelly's 3.58 ERA wasn't just a small sample fluke. He also had a 2.91 xFIP and 3.14 SIERA. That includes Kelly's final start of the season, giving up five earned runs against the Padres (5.2 IP). And two starts were shortened due to leg cramping.
We can't ignore the cramping as it's something Kelly dealt with in 2023 too. At 36 years old, cramping will probably occur again in 2025. But what Kelly did on his return to the mound was what fantasy managers would have expected when drafting him. Arguably the best thing was Kelly's velocity.
Over the entire 2024 season, Kelly's fastball velocity did drop. After averaging 92.2 MPH in 2023, it averaged 91.9 MPH in 2024. Only a slight drop but even that isn't something to be concerned about. If we break down Kelly's season, the drop in velocity can be attributed to the starts immediately after his return from the IL.
Kelly's four-seam fastball averaged 92.3 MPH in the four starts before his shoulder injury. It then averaged 90.9 MPH in his first three starts following his activation from the IL. In Kelly's last six starts of the season, his fastball averaged 92.2 MPH. It was a similar story for his sinker and cutter.
A 36-year-old pitcher with regular cramping issues who missed four months with a shoulder injury the year before doesn't sound like someone you should be targeting in drafts. However, Kelly had made 90 starts (536.0 IP) in the three seasons prior to 2024.
And the signs are that you can take Kelly with one of your last picks in the draft. Early NFBC drafts have Kelly going outside the top 80 starting pitchers taken. I'd have absolutely no hesitation in drafting Kelly in the 20th round. At that point, even 25 starts and a 4.00 ERA would provide value.
Nick Martinez, SP, Cincinnati Reds
Season numbers: 142.1 IP, 10-7 W-L, 3.10 ERA, 1.03 WHIP, 116 K
September numbers: 32.2 IP, 4-1 W-L, 0.83 ERA, 0.67 WHIP, 30 K
After spending most of the year as a reliever, few fantasy managers would have even noticed when Martinez re-joined the Reds' rotation in August. Martinez did begin 2024 as a starter but went to the bullpen after two starts. He made a further three starts settling into a full-time relief role in May.
Martinez's first five starts weren't going to keep him in the rotation. He allowed 21 earned runs (22.2 IP). By the time of his fifth start on May 22, Martinez had featured out of the bullpen six times (17.1 IP). He had a 1.04 ERA out of the bullpen.
Reds relievers had a combined 4.08 ERA as of May 22, so it was a bullpen that needed some stability. Martinez certainly helped that. His last appearance in relief came on August 2. Martinez was one of the best relievers in the league at that point, with a 1.86 ERA out of the bullpen (53.1 IP).
Given his struggles as a starter, Martinez drew very little interest as a fantasy option when he made his sixth start of the season on August 5. Back-to-back starts without allowing a run (12.0 IP) put Martinez back on fantasy manager's radars.
His next four starts (18.2 IP) saw Martinez give up 14 earned runs. By the time calendars flipped over to September, Martinez was once again 'persona non grata' for fantasy managers. That's when he excelled. Martinez made five starts (32.2 IP) in September and allowed just three earned runs.
Martinez impressed so much that the Reds extended a qualifying offer to him, worth $21.05 million. Cincinnati wouldn't have done that without envisioning Martinez as a member of their starting rotation in 2025. And there's reason to believe he can build on September's numbers and have success in 2025.
The below table shows Martinez's numbers as a reliever and a starter since 2022. There's no denying that Martinez has better numbers in relief. However, his numbers as a starting pitcher certainly warrant attention. If he put up those numbers across 184 innings in 2025, the Reds would be ecstatic.
| Role | IP | ERA | WHIP | xFIP | K% | BB% | wOBA | Hard% |
| Starter | 184.0 | 3.62 | 1.23 | 4.21 | 20.1% | 7.4% | .307 | 27.0% |
| Reliever | 175.0 | 2.98 | 1.11 | 3.58 | 22.9% | 5.9% | .281 | 22.2% |
Pitching in Cincinnati isn't ideal but Martinez manages to induce weak contact. For context, his 27.0% Hard% as a starter would have ranked as the seventh best among the 58 qualified starters in 2024. His .307 wOBA would have ranked 36th among the group.
The main concern with Martinez should be the workload. His 142.1 IP in 2024 was a career-high. Drafting a 34-year-old pitcher who just threw the most innings of his career might not seem like a great idea.
But given Martinez will largely be available as the last pick of your draft, he's worth gambling on. Things clicked for Martinez as a starter to close out the 2024 season. If he can build on that for 2025, Martinez could be one of the best value picks in your drafts.
Luke Weaver, RP, New York Yankees
Season numbers: 84.0 IP, 7-3 W-L, 2.89 ERA, 0.93 WHIP, 103 K, 4 Saves
September numbers: 12.0 IP, 3-0 W-L, 1.50 ERA, 0.75 WHIP, 25 K, 4 Saves
If Martinez converting from a reliever to a starter worked out well, Weaver converting from a starter to a reliever went incredibly well. Weaver was outstanding out of the bullpen all season. But it wasn't until he took over the closer role in September that Weaver really thrived.
Of course, in standard leagues, relievers not picking up saves aren't generally valuable. Clay Holmes' league-leading 13 blown saves almost forced the Yankees into a change. And Weaver's impressive numbers throughout the year made him the leading candidate to replace him.
Weaver's numbers make him the prototypical closer. A high number of strikeouts (31.1% K%), a high-powered fastball (95.7 MPH), and a nasty changeup (48.0% Whiff%) will likely lead to Weaver closing for the Yankees in 2025. His numbers point towards that being the case.
The Yankees have already exercised their club option for 2025. Meanwhile, Holmes is a free agent. So is their other closer candidate, Tommy Kahnle. It remains to be seen if the Yankees try to re-sign either of them. Even if they did sign one (or both), it was Weaver who went into the playoffs as the Yankees closer.
Weaver is currently being taken around 15th among relievers. That is largely due to uncertainty regarding his role in 2025. As of now, all signs point to Weaver being the closer in the Bronx. The Yankees will be seeking to sign Juan Soto. They also need a first baseman and second baseman.
If they spend on their offense as expected, they may not be in the market for any of the big-name free-agent relievers. That will leave the door wide open for Weaver to be a top 5 closer in fantasy next year.
Download Our Free News & Alerts Mobile App
Like what you see? Download our updated fantasy baseball app for iPhone and Android with 24x7 player news, injury alerts, sleepers, prospects & more. All free!
More Fantasy Baseball Advice
