4 Fantasy Baseball Risers and Fallers - Jo Adell, Ryan Pepiot, Jose Altuve, Luis Castillo

September 12, 2025

Connelly's fantasy baseball risers and fallers for Week 24 of 2025. He assesses hitters and pitchers performing well and poorly to determine their future value.

Welcome, everyone, to another edition of RotoBaller’s Fantasy Baseball Risers and Fallers article series for Week 24 of the 2025 season! Today, I'll look at Jo Adell, Ryan Pepiot, Jose Altuve, and Luis Castillo.

Keeping up with the latest hitter and pitcher trends is a key component for a successful season, and RotoBaller is here to help fantasy managers! Each week, I will select a few players who have performed well recently and a few who have not, and I will analyze their performances to determine how their future outcomes may be affected.

At this point in the season, fantasy playoffs are likely underway. Roster decisions have significant implications in head-to-head matchups, and a single bad outing can ruin roto rankings. Let's get into some Fantasy Risers and Fallers to help ensure you are ready to go!

Fantasy Baseball Hitter Riser

All stats are current as of Sunday morning, September 7, 2025

Jo Adell, Los Angeles Angels (OF)

.243/.304/.503 Slash Line, 34 HRs, 92 RBI, 5 SBs

Adell has been on and off fantasy radars for some time now. He has been a fantasy hopeful since 2020, but has not yet put it all together. He has brought the power this season and has been excellent the last two weeks, slashing .306/.346/.653 with five home runs, 13 RBI, and two stolen bases. Could he propel fantasy managers in the final few weeks?

Adell has taken a better approach at the plate this season. He owns a poor career 30.2% strikeout rate, but has cut that to a reasonable 25.9% this season. He has also impacted the ball harder than ever. His 91.5-MPH average exit velocity and 49.4% hard-hit rate are the best of his career.

Jo Adell - Los Angeles Angels (34)
pic.twitter.com/erouWg4fVp

— MLB HR Videos (@MLBHRVideos) September 7, 2025

These changes may not show in his season batting average, but they are impacting his numbers now. Adell has a .279 expected batting average on the season, so his recent .306 average appears to be raised due to overdue regression.

Adell has long been considered a potential impact fantasy player. It has taken him a while to figure things out, but he is finally producing like the player fantasy managers were hoping for. He will likely be a relevant name in drafts next season, and he looks like a legitimate fantasy player for the rest of the season.

Fantasy Baseball Pitcher Riser

All stats are current as of Sunday morning, September 7, 2025

Ryan Pepiot, Tampa Bay Rays

11-10, 3.59 ERA, 1.13 WHIP, 24.6% Strikeout Rate, 163 IP

Pepiot’s 2025 has gone pretty much exactly as his 2024 went. He has posted a solid 3.59 ERA, a 1.13 WHIP, and a 24.6%strikeout rate in 163 innings pitched. He has been on fire lately, allowing just two hits combined in his last three starts. Could Pepiot continue to cruise down the stretch?

One thing that stands out for Pepiot on the season is his batted-ball profile. He has given up a lot of hard, line-drive contact. His 90.3-MPH average exit velocity and 16.1-degree launch angle have led to a 3.96 ERA and a 4.01 SIERA that are higher than his current ERA.

His batted-ball profile has actually been worse in his last three games than his season marks. He allowed a 50% hard-hit rate, a 92.4-MPH average exit velocity, and a 15.6-degree launch angle on 30 batted balls. Despite this, he experienced a minuscule .067 BABIP.

He did experience a bump in strikeouts with a 28.8% strikeout rate. Pepiot typically relies heavily on his four-seam fastball. He leaned into his fastball-changeup combo in the last three games, with 54.5% fastball usage and 25.2% changeup usage. This simplified pitch-mix approach was effective in generating strikeouts, as 14 of his 15 strikeouts came on those two pitches.

Ryan Pepiot, Filthy 87mph Changeup. 😷

5th K pic.twitter.com/i0sYaKYOS6

— Rob Friedman (@PitchingNinja) September 5, 2025

Overall, it seems as though Pepiot definitely got lucky in his last three games. He allowed plenty of hard contact but yielded just two hits. It wasn't all smoke and mirrors, as his strikeout boost was encouraging. Pepiot's next start will be a favorable one at the White Sox, so I would be fine riding the hot hand for at least that matchup.

Fantasy Baseball Hitter Faller

All stats are current as of Sunday morning, September 7, 2025

Jose Altuve, Houston Astros, (2B/OF)

.266/.331/.446 Slash Line, 24 HRs, 69 RBI, 9 SBs

Altuve is having a fine fantasy season overall, but he is having a down season by his standards. He has particularly struggled in the second half, slashing just .212/.288/.386 since the beginning of August. At 35 years old, Altuve has provided plenty of high-end fantasy seasons. Could he actually be a detriment to fantasy managers at the end of this season?

Altuve's stats from August onward compared to the season are puzzling. Everything across the board, from his walk rate to his strikeout rate, his average exit velocity, his HR/FB rate, and his pull-air rate, is all in line between his season marks and his second-half marks. These marks are also not out of line with his career marks, making his struggles even more puzzling.

The two differences that stand out are changes in BABIP and swinging-strike rate. Altuve has managed a poor .214 BABIP from August onward, compared to a .282 BABIP in 2025 and a .326 BABIP for his career. He has also swung and missed more during his slump, with a 10.8% swinging-strike rate compared to 8.9% on the season.

It is hard to pinpoint a true reason to have concern about Altuve other than his recent performance. He has missed more pitches lately and has chased more pitches this season overall, but his approach led to solid production earlier in the season.

The Astros are in the thick of a playoff run, and Altuve should continue to bat at the top of a strong lineup. He will have to play more games outside of Daikin Park the rest of the way, but I'm not sure I could pull the trigger on giving up on him, given his track record and lack of clear decline evidence.

Fantasy Baseball Pitcher Faller

All stats are current as of Sunday morning, September 7, 2025

Luis Castillo, Seattle Mariners

8-8, 3.94 ERA, 1.29 WHIP, 21.0% Strikeout Rate, 155 1/3 IP

Castillo has often been thought of as a high-floor, safe fantasy starter. His numbers this season have been ok, but they have not been as strong as in previous seasons. This has been due to a poor second half where Castillo has posted a 5.17 ERA, a 1.43 WHIP, and a 21.8% strikeout rate in nine starts. Can fantasy managers trust him for the rest of the season?

Castillo has given up a lot of hard contact in the second half. His 92.5-MPH average exit velocity and 13.3-degree launch angle have not been a recipe for success, even while pitching five starts in pitcher-friendly T-Mobile Park. All his hard contact has led to a lot of baserunners with a .348 BABIP.

Additionally, it has led to a lot of HR. Castillo has allowed at least one HR in each of his last six starts, leading to nine total and a poor 1.72 HR/9 rate. It has also led to a 15.5% HR/FB rate, which, while not objectively awful, is higher than his 13.7% career mark.

All of his batted-ball woes have limited Castillo's outings. He typically could be counted on to pitch relatively deep into games, but four of his nine second-half starts have lasted fewer than five innings. This has limited Castillo's fantasy upside in points leagues, where his poor ratios have tanked his roto value.

Castillo has been unreliable in the second half. He has allowed a lot of hard contact, leading to a lot of baserunners and a lot of HR. His next matchup will be at home against the strikeout-prone Angels. I would be inclined to risk it in a points format, but I'm not sure I could trust Castillo in roto leagues.

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