Eric Cross' Fantasy Baseball Waiver Wire Pickups - Hitters and Pitchers (Week 21)

Eric Cross' top fantasy baseball waiver wire adds for Week 21 of 2025 (August 18 - August 24). His favorite free agent hitters and pitchers under 40% rostered.

We've reached the point in the season where the word "grind" takes on extra meaning. We've been setting lineups, making trades, and scouring the waiver wire for nearly five months now, and fantasy football has crept into the picture for some of you. But staying diligent with your teams and staying on top of the waiver wire is just as important now as it was in April and May.

The players below are all under 40 percent rostered in Yahoo! leagues. Some of them might already be rostered in your leagues, but if they're available, I'd recommend considering them to see if they could be good fits for your fantasy teams.

Last week's recommendations were Luke Keaschall, Jakob Marsee, Isaac Collins, Carlos Correa, Matt Wallner, Cade Horton, and Jacob Lopez.

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Sal Frelick (OF - MIL)

36% Rostered on Yahoo

It's actually a bit surprising that Sal Frelick is still available in over 60% of Yahoo leagues. Sure, he isn't the buzziest or most exciting player around, but we're still talking about a player on pace for 78 runs, 12 home runs, 63 RBI, and 24 steals while slashing .298/.361/.416.

While he's never been much of a power hitter, Frelick isn't a zero in the HR and RBI categories while providing solid contributions in AVG, OBP, runs, and stolen bases. Frelick has posted a 90.2% zone contact rate, 87.7% overall contact rate, and has struck out just 12.8% of the time this season while having an 87th percentile sprint speed. He's also Milwaukee's primary leadoff hitter against right-handed pitchers. Not every waiver wire pickup has to be a sexy potential league-winner.

Blaze Alexander (2B/3B/SS - ARI)

30% Rostered on Yahoo

Ever since Eugenio Suarez was traded to Seattle, Blaze Alexander has been blazing at the plate. In his last 12 games, Alexander is slashing .317/.429/.683 with three doubles, four home runs, nine RBI, and seven runs scored. He was also having a decent season down in Triple-A with a .284/.413/.479 slash line in 54 games along with 12 doubles, eight home runs, and 11 steals.

The Life of a Showman pic.twitter.com/CkJvkIFisf

— Arizona Diamondbacks (@Dbacks) August 13, 2025

When you pop the hood on Alexander's profile, you'll find plenty of metrics to be encouraged by. He's been hitting the ball hard during his time with Arizona, posting an impressive 13.4% barrel rate, 91.8 mph AVG EV, and a 46.3% hard-hit rate. On top of that, Alexander has an 86th percentile sprint speed.

However, the contact skills, both in zone and overall, are well below-average, which probably won't lead to a higher average the rest of the season. But if Alexander can just hit .250 to pair with good power and a steal here and there, he can still provide useful fantasy value to those who add him right now.

Noelvi Marte (3B/OF - CIN)

25% Rostered on Yahoo

Given how he's performed and his former top prospect status, it's odd to see Noelvi Marte still available in 75% of Yahoo leagues right now. Maybe the sour taste he left in fantasy managers' mouths last season after being suspended for the first half of the season and performing terribly at the plate in the second half was sour enough to create hesitation when looking to add him this season.

Noelvi Marte comes through with a BIG home run in the 9th! pic.twitter.com/GdBftzZakY

— MLB (@MLB) August 10, 2025

In 199 plate appearances this season, Marte is slashing .289/.327/497 with 27 runs, eight home runs, 36 RBI, and seven steals. That's a 650 plate appearance pace of 88 runs, 26 home runs, 118 RBI, and 23 steals. You're going to leave that just sitting on your league's waiver wire? Especially now that he has dual 3B/OF eligibility?

While Marte's contact rates are slightly below-average right now, his power metrics are trending in the right direction with a 38% hard-hit rate in the second half and a 12.5% barrel rate so far in August. Marte is also a 90th percentile runner who has cut his strikeout rate from 31% last season to 19.1% this season. Although he's still not walking much at a 4% clip.

Chandler Simpson (OF - TBR)

32% Rostered on Yahoo

Listen, I understand that adding players who provide you with absolutely nothing in two of the five standard fantasy categories can often make the player less appealing. Chandler Simpson is definitely one of those players, but he can provide your fantasy teams with value with what he brings to the table outside of home runs and RBI.

Simpson is currently tied for third in the Majors with 34 steals, and he's only been up with the Tampa Bay Rays for 74 games. If he had been up with them for another week or two, Simpson would likely be your Major League steals leader right now. If he had been up for the entire season, he'd be first by a country mile.

Outside of speed, Simpson also brings a high average to any fantasy team that he's on. Simpson is hitting .307 in 287 Major League plate appearances this season, which is the eighth-best mark out of anyone with at least 250 plate appearances. That .307 AVG is legit in my eyes as Simpson is running a 90.8% zone contact rate, 89.1% overall contact rate, and has a 99th percentile sprint speed. He also has a 650 plate appearance pace of 82 runs scored.

Joey Ortiz (3B/SS - MIL)

13% Rostered on Yahoo

Overall, it's been a disappointing season for Joey Ortiz in Milwaukee, but he's been heating up at the plate of late. In 55 plate appearances this month, Ortiz has slashed .392/.436/.529 with seven doubles, two steals, 11 RBI, and 13 runs scored while only striking out in 5.5% of his plate appearances. Ortiz has also seen his hard-hit rate tick up to 37.5% this month, and his 90th percentile EV is barely below William Contreras' mark.

While the quality of contact metrics hasn't been overly impressive this season, Ortiz has always been better under the hood than his slash line through the end of July would indicate. Ortiz has posted an 88.3% zone and 84.2% overall contact rate in 2025 with a 15% strikeout rate and a contact rate of 76% or better against all three pitch types. So while I wouldn't expect many home runs, Ortiz can provide a solid AVG and some steals as well down the stretch. The dual 3B/SS eligibility can be beneficial as well.

Nolan McLean (SP - NYM)

20% Rostered on Yahoo

The New York Mets have promoted right-handed pitching prospect Nolan McLean from Triple-A Syracuse to make his Major League debut on Saturday against the Seattle Mariners. In 113.2 innings between Double-A and Triple-A this season, McLean recorded a 2.45 ERA, 1.13 WHIP, and a 27.2% strikeout rate. The walk rate was a bit high at 10.7%, but that's not a major concern for McLean moving forward.

McLean has a deep six-pitch mix, headlined by one of the best sweepers you'll ever see. The mid-80s offering has been McLean's best pitch in the minors and has an average spin rate over 3,000 RPMs. McLean's curveball has an even higher spin rate, averaging over 3,300 RPMs.

While his debut matchup against Seattle isn't an easy one, McLean has the upside to warrant a look in all 12-team leagues or deeper moving forward.

Hurston Waldrep (SP - ATL)

34% Rostered on Yahoo

Since debuting for the Atlanta Braves on August 2, Hurston Waldrep has been nothing short of amazing. In 17.2 innings in his three outings, Waldrep has a 1.02 ERA, 0.79 WHIP, a 7.6% walk rate, and a 25.8% strikeout rate. In his last outing against Cleveland on Friday, Waldrep tossed six shutout innings with seven strikeouts and 14 whiffs, 13 of those coming on his splitter and slider.

Waldrep's splitter has always been his bread and butter offering, and that has been apparent so far in the Majors as the offering has a .048 BAA, .048 SLG allowed, and a 54.3% whiff rate as Waldrep's most used offering. But with that said, Waldrep's arsenal has evolved this season as he's added a cutter around 93 mph and a sinker in the mid-90s to his splitter, 4-seamer, slider, and curveball.

Given how depleted the Atlanta rotation is right now, I'd expect Waldrep to get plenty of run over the final six weeks of the season.

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