Hitter Fantasy Baseball Breakouts - Risers to Watch and Waiver Wire Outlooks (Week 15)

Jarod's hitter fantasy baseball breakouts, sleepers, and risers to watch for Week 15 of 2025. His list includes waiver wire outlooks and underachieving hitters so far.

Welcome back to my Fantasy Baseball Breakout Hitters article for Week 15 of the 2025 MLB season. The focus of this article is to highlight players who could be on the verge of a breakout, citing current active hitting streaks along with recent leaders in batting average and isolated power (ISO). You will also find expected batting average (xwOBA) underachievers and overachievers for the second time this season!

In this week's edition, we'll dive into players like Jo Adell, Kyle Stowers, and Corey Seager. You'll not only find out who is hot at the plate but also which hitters deserve better results based on their expected stats or who might be on the verge of a cold spell.

Last week, Yandy Diaz and Brenton Doyle were a couple of good callouts who kept on hitting. So, let's take a closer look at our breakout watch to help your fantasy baseball teams heading into Week 15. You might find a potential waiver wire target or some worthy DFS plays!

• Fantasy baseball trade analyzer
• BvP matchups data (Batter vs. Pitcher)
• PvB matchups data (Pitcher vs. Batter)
• Who should I start? Fantasy baseball comparisons
• Daily MLB starting lineups
• Fantasy baseball closer depth charts
• Fantasy Baseball live scoreboard
• Fantasy baseball injury reports

Hit Streak Leaders

Data through 7/2

Brandon Lowe (18 games)

Brandon Lowe was in this article back in May when he recorded a 13-game hit streak, and here he is again with an 18-gamer, during which time he's gone 27-for-71 (.380) with six home runs, 14 RBI, and 18 runs scored.

Now the 30-year-old has his slash line up to .274/.324/.495, and with 19 home runs in 307 at-bats, he's on pace for 30-plus home runs. Hitting in front of the likes of Junior Caminero should ensure plenty of run-scoring production through the end of the season as well.

Jo Adell (13 games)

Jo Adell was mentioned in last week's article, but I added that he's more of a power guy who doesn't hit for average. Yet here he is again, now with a 13-game hit streak where he's hitting for average.

June was nothing,

WELCOME JO JULY ADELL 🔥

pic.twitter.com/pOyl5TifzQ

— Jo Show Adell (@JoShowAdell) July 2, 2025

During this streak, the former first-round draft pick is slashing .340/.421/.680, recording a better-than-average 17.5 percent strikeout rate with a strong 12.3 percent walk rate. Adell has shown flashes of this in the past, but right now, he's got an xBA of .284 and an xwOBA of .394, suggesting this hot stretch has legs.

Together with his 80th-percentile hard-hit rate and 91st-percentile barrel rate, the 26-year-old looks like he could keep this up for a while longer. He's rostered in around 50 percent of Yahoo! leagues, which feels about right, but DFS users can certainly pencil him in more against both lefties and righties (142 wRC+ vs. LHP, 125 wRC+ vs. RHP)

(Update: Adell went 3-for-5 on Thursday, extending his hit streak to 14 games)

Highest Batting Average Last Seven Days

Data through 7/2, minimum 13 at-bats

I usually write up a hitter or two in depth here, but there are so many intriguing names on this list that I think I will give a quick blurb about a handful of them instead of just a couple.

Zach McKinstry (.524 BA)

Zach McKinstry has shown up here a couple of times already this season, so he's having a great year,  slashing .290/.361/.456 with five home runs and 10 steals, but add in the fact that he's eligible at 2B, 3B, SS, and OF, and you have yourself a nice fantasy asset who is available in over half of leagues.

(Update: McKinstry went 1-for-3 on Thursday)

Cam Smith (.478 BA)

Cam Smith has five multi-hit games in his last six games, and since June 11, he's gone 29-for-78 (.372) with four doubles, four home runs,15 RBI, 14 runs scored, and a stolen base. The former first-round draft pick has batted cleanup in five straight, making him all the more valuable in DFS.

Cam Smith pays a visit to the train tracks! 🚂 pic.twitter.com/j9J5CF0C2n

— MLB (@MLB) June 28, 2025

(Update: Smith went 3-for-5 with three RBI on Thursday)

Christian Koss (.474 BA)

Christian Koss was just placed on the 10-day IL with a hamstring strain, but don't forget about him when he comes back. The 27-year-old had a mini five-game hit streak going before the injury, four of which were multi-hit performances, going 9-for-19 with three doubles in those five games.

He's available in nearly all leagues and is eligible at 2B, 3B, and SS on Yahoo!

Colt Keith (.471 BA)

Colt Keith has begun to swing a hot bat, and although he's posting similar contact rates compared to 2024, he's chasing five percent less, barreling five percent more, and registering an eight percent higher hard-hit rate.

He's also playing multiple positions, eligible at 1B, 2B, and 3B, and is rostered in just 14 percent of leagues. The 23-year-old had a 27-homer campaign in the minors in only 126 games, so there is potential to eclipse his home run total of 13 from 2024 if he gets the power stroke going.

(Update: Keith went 1-for-4 with two runs scored on Thursday)

Caleb Durbin (.462 BA)

Look out if Caleb Durbin gets hot, he could start running wild on the basepaths. The 25-year-old recorded three straight seasons of 30-plus steals in the minors led the Arizona Fall League in steals two consecutive years and swiped 10 bags in 18 games this spring.

His 9.4 percent K% puts him in the 98th percentile, and he's making contact at a good 87.9 percent rate, so expect him to keep putting the bat on the ball. Like some others listed here, he's got low rostership (16 percent) and is eligible at multiple positions (2B, 3B, SS).

(Update: Durbin went 1-for-3 with a walk and an RBI on Thursday)

Highest ISO Last Seven Days

Data through 7/2, minimum 13 at-bats

Spencer Steer had the highest ISO, but much of his production came in a single three-homer game, and he is now dealing with a hand contusion that has rendered him day-to-day.

Kyle Stowers  (.667 ISO)

Kyle Stowers showed good pop earlier this year, belting 10 home runs by mid-May, but then he experienced a serious power outage, going homer-less in 31 straight games. However, the left-handed slugger has found the groove again, blasting five home runs in his last nine games, with four doubles to boot.

KYLE JACOB STOWERS pic.twitter.com/WUuW7ACSVy

— Miami Marlins (@Marlins) July 2, 2025

While he doesn't display much power against left-handed pitchers, he still hits them well and gets on base at a good rate, slashing .317/.380/.413 against LHP compared to .272/.350/.545 against RHP. At just 51 percent rostered, you can get an outfield bat who is already up to 15 home runs on the year.

(Update: Stowers went 0-for-3 on Thursday)

Most Steals Last Seven Days

Data through 7/2

Dane Myers was included in my Week 13 article, where I stated, "It feels like fantasy managers could be buying low here, getting a hot hitter with stolen base upside." Well would you look at that, five steals in the last week, more than any other player!

Willi Castro (three SBs)

Neither Myers of Willi Castro have much to talk about in the way of hitting, though, as Myers had zero extra-base hits in the last week and Castro had just two doubles, however, the latter stole three bases in the previous week, which is somewhat eye-opening since he only had three all season prior to that.

If this is the beginning of a trend, then it could be time to get on board, as the 28-year-old utility man can provide serviceable hitting (.275/.358/.440), is available in over half of leagues, and is eligible at 2B, 3B, SS, and OF.

(Update: Castro went 0-for-3 with a walk and another stolen base on Thursday)

xwOBA Underachiever

Data through 7/2

At the beginning of the season, this section examined hitters due for a bounceback in batting average, followed by an analysis of hitters with significant discrepancies in xSLG. This week, I'll take a look at hitters with some of the most significant differences in wOBA and xwOBA.

Corey Seager (.345 vs. .411)

When Corey Seager has been on the field, he's one of the best hitters in baseball, but staying on the field has been a challenge for him. The perfect example of this is 2023 and 2024, where he hit at least 30 home runs but played in no more than 123 games. The 5x All-Star has already missed time this season as well but is healthy right now and riding an eight-game hit streak.

Corey Seager sends this homer 420 feet 🚀 pic.twitter.com/3lIbeTKUEZ

— MLB (@MLB) July 3, 2025

During the streak, he's gone 10-for-30 (.333) with two doubles and four home runs, yet he still owns one of the highest wOBA vs. xwOBA differentials in the entire league. Although the 31-year-old's contact rate is down this season, so too is his chase rate, while the left-handed slugger's barrel rate is good at 14.5 percent, and his hard-hit rate is the second highest of his career (53.5 percent).

Look for the veteran to continue to hit, and this eight-game hit streak should have plenty of room to run.

xwOBA Overachiever

Data through 7/2

Gavin Lux (.339 vs. .310)

Gavin Lux isn't knocking the cover off of the ball this season but has posted a solid .273/.365/.394 slash line with a .339 wOBA and 112 wRC+. But while he's making good contact (8.0 percent swinging-strike rate) and isn't chasing pitches (95th percentile), the former first-round draft pick's barrel and hard-hit rate sit at a career-low 3.8 percent and 36.6 percent, respectively.

The 27-year-old is middling in the speed department, so he's not going to consistently beat out infield singles, and his BABIP is a tad frothy at .358 compared to a career average of .321.

At 10 percent rostered, most managers aren't in need of or looking for his services, but Lux could go cold here and could probably be avoided in DFS most days, too.

More Fantasy Baseball Advice