Hitter Fantasy Baseball Breakouts - Risers to Watch and Waiver Wire Outlooks (Week 23)

August 30, 2025

Jarod's hitter fantasy baseball breakouts, sleepers, and risers to watch for Week 23 of 2025. His list includes waiver wire outlooks and underachieving hitters so far.

Welcome back to my Fantasy Baseball Breakout Hitters article for Week 23 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, stolen bases, and isolated power (ISO).

This week, we'll check in on some hot names like Mark Vientos, Colson Montgomery, and Dansby Swanson. We'll also take a look at a guy who has been hitting well all season, but may be unsustainably hot right now and could see a dropoff over the final month of the season.

Who should fantasy managers look to grab off the waiver wire or even plug into their DFS lineup this week? Let's check it out below!

Hit Streak Leaders

Data through 8/27

We finally have a hit streak leaders list that looks like something we're used to, with many of the usual suspects like Bobby Witt Jr., Bo Bichette, and Bryce Harper included in it. There is one notable name on this list, though, and that's who we'll talk about.

Mark Vientos (10 games)

Mark Vientos came into the season with high expectations after a breakout in 2024; however, the season has not gone as he or fantasy managers who drafted him had hoped.

The 24-year-old is seemingly finally rounding into the form he showed much of last year, currently riding a 10-game hit streak, during which time he's gone 15-for-38 (.395) with four doubles, six home runs, 17 RBI, and eight runs scored.

Mark Vientos is HOT 🔥

He's got 6 homers and 17 RBI in his last 10 games! pic.twitter.com/Vn9mgHU2Dz

— MLB (@MLB) August 28, 2025

The former second-round draft pick's chase and contact rates are little changed compared to his season-long numbers, but he's hitting the ball hard, recording a 64.5 percent hard-hit rate and a 29.0 percent barrel rate.

So even if he doesn't stay quite as hot, the power should remain. The right-handed slugger is rostered at 72 percent in Yahoo! leagues, up 25 percent from this time last week, so he won't be found on many waiver wires, but managers looking for some production in that area should take a peek.

Highest Batting Average Last Seven Days

Data through 8/27, minimum 13 at-bats

Jesus Sanchez (.556 BA)

Raise your hand if you hung with Jesus Sanchez on and off this year despite mediocre results, then watched him go 0-for-27 and dropped him in disgust, only to see him collect five hits in the very next game and record multiple hits in three of the last four games he started (my hand is raised).

Jesús Sánchez records his second career 5-hit game 👏 pic.twitter.com/KFdbjU1Z9P

— MLB (@MLB) August 22, 2025

He's 10-for-17 (.588) in those four games, including two doubles and two home runs. The left-handed slugger is not going to play every day, which makes him additionally frustrating in season-long leagues, but he should be in play for DFS against right-handed pitchers (.129/.194/.210 vs LHP, .277/.335/.458 vs. RHP).

Jared Triolo (.476 BA)

Jared Triolo popped up in last week's article for having the most stolen bases during the prior week, but I mentioned that if you ignore his season-long numbers and just look at August, he's been hitting well this month.

Since then, the 27-year-old recorded five consecutive multi-hit games during the last week, which included a double, a triple, and two home runs. That brings his August slash line to .329/.424/.494 in 93 plate appearances. He even swiped another bag as well.

Jared Triolo breaks the scoreless tie with his second homer in as many games 💪 pic.twitter.com/4iGqfnFKYv

— MLB (@MLB) August 24, 2025

For those looking for a hot bat, Triolo is just 24 percent rostered (up 23 percent from last week!) and is eligible at 1B, 2B, 3B, and SS.

Highest ISO Last Seven Days

Data through 8/27, minimum 13 at-bats

Colson Montgomery (.765 ISO)

Although he's always been one of Chicago's top prospects, it was a bit surprising to see Colson Montgomery get a promotion to the big leagues with a .215 batting average and 33.0 percent strikeout rate this season at Triple-A. He had tallied 11 home runs in 60 games, though.

His season in the bigs looks a lot like the minors, with a .230 batting average and a 27.3 percent strikeout rate, but with lots of power. The former first-rounder has 14 home runs in just 43 big league games, which is a 50+ homer pace in a 162-game season.

Colson Montgomery has homered in FOUR straight games!

14 HR in 43 career games for the @WhiteSox rookie 😤 pic.twitter.com/jToJXtd3E8

— MLB (@MLB) August 27, 2025

He's currently riding a four-game home run streak, so he hasn't slowed down. The one thing standing in his way could be his health. The 23-year-old is dealing with soreness in his side, which kept him out of Wednesday's lineup, so keep an eye on whether or not it leads to an injured list stint.

Supposedly, he's been playing with the soreness, which obviously hasn't diminished his ability to hit for power. For managers who can deal with potentially sacrificing batting average for home runs, Montgomery is available in over 60 percent of leagues.

Most Steals Last Seven Days

Data through 8/27

Austin Martin (four SBs)

There are some highly rostered names on this list, but Austin Martin sticks out like a sore thumb. Martin was called up on August 1 and has been on the short end of a platoon, leading to limited playing time.

Despite the limited playing time, he's tallied four of his six stolen bases in the last week alone, and has hit .254 this month. The contact rate is good at 85.3 percent with a low 15.5 percent strikeout rate, so keep an eye out; if he earns more playing time, a slight rise in batting average and steals could follow.

This is a nice sight! Austin Martin shows off some power#MNTwins
pic.twitter.com/Uq2GB9PYgW

— Twins Talk (@LetsTalk_Twins) August 6, 2025

At zero percent rostered, though, taking a chance on him now would certainly qualify for getting in at the ground floor. The 26-year-old is eligible at both 2B and OF, providing some added appeal.

xwOBA Underachiever

Data through 8/27

Dansby Swanson (.303 vs. .353)

Dansby Swanson's 2025 season has looked a lot like his past couple of seasons in terms of batting average, strikeout rate, contact rate, BABIP, and wRC+, but his barrel rate is 2.4 percent higher than last year, and his hard-hit rate is 4.4 percent higher.

It has led to an 18-homer campaign, already two more than he hit all of last season. What's more is that his xBA is 31 points higher than his actual batting average, xSLG is 91 points higher than SLG, and xwOBA is 50 points higher than wOBA.

It all points to continued production in the power department, but with potential for an increase in batting average as well, which would likely help his counting stats, too.

xwOBA Overachiever

Sal Frelick (.339 vs. .306)

Sal Frelick is having a productive season, hitting .287 with nine home runs, 18 steals, a .339 wOBA, and a 119 wRC+. August has been his best month yet, slashing .320/.407/.427 with a .370 wOBA and a 140 wRC+ in 20 games, even walking (11) more than he's striking out (10).

A .359 BABIP in the month is on the unsustainable side, though, and with a big difference in wOBA and xwOBA, a dropoff could be coming. With a 90.0 percent contact rate, the 25-year-old should still be able to put the bat on the ball with regularity and can be plenty productive, but don't expect outperformance in September.

More Fantasy Baseball Advice