There were plenty of rookies who made a strong impact in the majors last year. Players like Paul Skenes, Jackson Merrill, and Shota Imanaga were consistent for most of the season. Then, there were players like Jackson Chourio, Luis Gil, and Colton Cowser. All three players had some ups and downs, but they also had some elite stretches throughout the year.
In a separate category were rookies who surged in September. These players might not have seen many opportunities early in the season or got off to a slow start. However, they showed their potential in the final month of the season and could wind up being sleepers in 2025 fantasy baseball drafts.
So, which four rookies surged in September? Should these players be selected in fantasy baseball drafts? Let's dive in and find out.
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Otto Lopez, 2B, Miami Marlins
Miami Marlins second baseman Otto Lopez finally got his shot in the big leagues in 2024. After the San Francisco Giants designated him for assignment on April 1, the Marlins claimed him just a couple of days later. Although Lopez didn't start the season in the majors, he did find himself on the major league roster only two weeks into the new campaign.
However, like most rookies, Lopez went through the ups and downs in his first year. He looked solid at the plate through the first month before struggling mightily from June to August. During those two months, the Marlins second baseman hit .230 with zero home runs, 12 doubles, and 10 RBI.
Following that rough stretch, though, Lopez finally surged in the final month of the season. He was a more disciplined hitter and was finally making strong contact at the plate. That led to the young infielder hitting .344 with three home runs, eight doubles, 14 RBI, and four stolen bases across 25 September games.
#Marlins Otto Lopez was one of the better defensive 2B in MLB in ‘24
- 3rd in Outs Above Average (Semien and Giménez)
- 3rd in Total Defensive Value (Semien and Giménez)And he did this in ~500 less innings than both Semien and Giménez
Absurdly underrated if he repeats success pic.twitter.com/rb3MQnrLkz
— Danny (@DM__MIA) January 26, 2025
Lopez's surge in September is surely a nice sign heading into the 2025 campaign. Although the 26-year-old won't provide much power numbers at the plate, he can hit for a high average and could tally over 20 doubles this upcoming year. He could also steal upward of 20 bases this season, given that he did it in 2024 and has a sprint speed (28.7) that ranks in the 86th percentile in baseball.
Therefore, Lopez could be a sleeper pick later in fantasy baseball drafts. He will almost certainly open the season as the Marlins' starting second baseman and has every opportunity to build on his encouraging September.
Spencer Schwellenbach, SP, Atlanta Braves
Atlanta Braves starting pitcher Spencer Schwellenbach had a solid rookie campaign. He finished the year with a 3.35 ERA and 127 strikeouts across 123 2/3 innings pitched but also dealt with some struggles on the mound throughout the year. Schwellenbach gave up at least four earned runs in four of his first nine starts and entered August with a 4.06 ERA.
However, the right-hander took his game to a new level in September. He had some dominant outings on the mound during this month, which included tossing six innings of two-run ball against the Dodgers on September 13 and seven innings of one-run ball against the Mets on both September 24 and September 30. Those performances helped Schwellenbach finish the month with a 2.25 ERA across six starts.
As a result, the Braves pitcher could wind up being a great selection in fantasy baseball drafts. He had a nice rookie season and surged in the final month of his rookie campaign. Schwellenbach's metrics from last year also suggest that his September splits were no fluke. His 34.2 percent chase rate, 4.6 percent walk rate, and 4.9 percent barrel rate against all ranked in the 90th percentile or better in 2024.
Six starting pitchers had 2+ offerings with a 40+% whiff rate in 2024, min 200 pitches for each offering.
Blake Snell (3)
Tyler Glasnow
Jesús Luzardo
Reese Olson
Spencer Schwellenbach
Kyle Gibson pic.twitter.com/aeMZ9MAB0Y— Eric Cross (@EricCrossMLB) January 8, 2025
Given the way Schwellenbach ended last season, he is a solid pick in the middle round of drafts. He doesn't walk many batters and should only improve on the mound in 2025.
Rhett Lowder, SP, Cincinnati Reds
Cincinnati Reds pitcher Rhett Lowder is in an interesting case heading into 2025 because he is the only player on this list who isn't guaranteed a roster spot entering the season. With Hunter Greene, Brady Singer, Andrew Abbott, Wade Miley, and Nick Lodolo all with the team, Lowder might not even make the Reds' Opening Day roster.
But he should at least have a shot to make it following a strong September last season. Lowder was called up by Cincinnati at the end of August to start a doubleheader against the Brewers and ended up spending the rest of the year with the major league club.
During this span, the Reds got the opportunity to finally see what their 2023 first-round pick was made of, and they weren't disappointed. Lowder made five starts in September and gave up just three runs in 26 2/3 innings of work (1.01 ERA). The right-hander also had four separate outings during this stretch of at least five innings pitched and zero earned runs allowed.
So, Lowder does have a chance to make Cincinnati's Opening Day roster. He showed a lot of great things on the mound in those five September starts, and opposing hitters had just a 3.3 percent barrel rate against him last season. However, the Reds might choose to prioritize some of their veteran pitchers to begin the season.
That means there's a strong chance that the 22-year-old begins the season down in Triple-A. If that does happen, fantasy managers should keep an eye on him throughout the year. He'll get his shot again in the majors and could wind up being a strong waiver wire pickup. If Lowder does make the Opening Day roster, he could be a value pick in the later rounds following his strong numbers in September.
Wyatt Langford, OF, Texas Rangers
There was a lot of hype surrounding Texas Rangers outfielder Wyatt Langford before his debut. He quickly rose up the minor league ranks during the 2023 season and hit .360 at the plate with 10 home runs and 30 RBI in 60 games across Rookie ball, High-A, Double-A, and Triple-A. As a result, this was a player many fantasy managers wanted to select in drafts last spring due to his upside.
Langford, though, struggled early on in his rookie season. He was hitting .227 with one home run, four doubles, and 15 RBI in his first 40 games, and his power just didn't seem to translate to the majors yet. While things did pick up for him offensively shortly after, the first couple of months were surely an adjustment period for him.
Then, something switched for Langford in the final month of the season. He was a much different hitter at the plate in September, and the production was finally there.
He had a .300 batting average (30-for-100) to go with eight home runs, seven doubles, 20 RBI, and seven stolen bases across 26 games in September. Those eight home runs ranked tied for fourth among all qualified hitters in September, and his 1.6 WAR was tied with Cal Raleigh for the second-highest during this month.
Wyatt Langford goes 110/35/110/25/.280 and is a Top 10 pick in 2026 drafts. https://t.co/bjdk3j9o5o
— Eric Cross (@EricCrossMLB) February 2, 2025
It was great to see Langford finally break through at the plate late last season, and there are reasons to believe that his September production is here to stay. His chase rate ranked in the 86th percentile -- which is elite for a rookie -- and his barrel rate (9.4 percent) and hard-hit rate (43.4 percent) numbers were solid, too. That makes him a strong pick early in 2025 fantasy drafts.
Honorable Mention
- Luisangel Acuna, INF, New York Mets
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