Wednesday Fantasy Baseball Starting Pitcher Streamers: Warren and Mahle Lead the Pack

Let's jump right in today and look at four starting pitchers in action on Wednesday who have good matchups and are widely available in fantasy leagues. 

Most stats are from MLB.com, as are the probable starters. The full streamer rankings are listed at the bottom.

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Luis Castillo, Chicago White Sox vs. Cincinnati Reds

Castillo was acquired from Seattle near the trade deadline after a disappointing first four months. He has given up too many hits, runs, and home runs, and though he has been good with walks, Castillo's strikeout rate is below average on the season after previously being very good in that area. He made his first start with the White Sox last Thursday against Boston, giving up six hits, five runs, and a homer in four innings with a walk and five strikeouts. Castillo has ace-level work in his past, but that pitcher hasn't been seen in 2026.

The Reds offer a better matchup than the Red Sox did last week, as Boston has been on fire the past few months. Cincinnati, on the other hand, ranks in the bottom 10 in most box stats, showing a season-long lack of offensive prowess. They do rank in the top 10 in walks and home runs; a team can find success with those marks. The Reds are in the bottom five in runs scored, though, along with several other categories, so that power hasn't translated to success. Cincinnati also strikes out at a top-three rate, setting a nice ceiling for opposing pitchers.

Castillo is a low-to-mid-level streamer. It's tempting to think that Castillo could figure things out with a change of scenery, but he just hasn't shown much in 2026, making it hard to trust him. The matchup is in his favor, though, and he could rack up some strikeouts if nothing else.

Tyler Mahle, Atlanta Braves vs. New York Mets

The Mets are on a bit of a hot streak, winning six of seven games before Tuesday (Atlanta shut them out yesterday). They averaged over seven runs per game in that stretch, giving us reason to second-guess targeting them with streaming pitchers. I can't get over their season-long numbers, though: New York ranks in the bottom 10 (or very close to it) in runs, hits, doubles, walks, batting average, on-base percentage, slugging percentage, and OPS. We can't ignore that the Mets have been better the past few months than they were at the beginning of the year, but this is still a team I'm looking to target many days.

Mahle is another pitcher who changed teams at the trade deadline, joining Atlanta from San Francisco. He sparkled in his first start with the Braves, throwing six shutout innings with three hits, two walks, and nine strikeouts against the Yankees (who have been struggling). This year, Mahle has been right at average with walks, strikeouts, hits, and home runs, but he has given up too many runs; it's fair to say that he's been a little unlucky. Mahle has been a solid pitcher in his career, and he's worth considering when the matchup is right.

Mahle is a mid-level streamer. It's easy to think he will shine with the Braves, who tend to get the best out of their pitchers, but we also shouldn't expect huge outings every time he takes the mound. While the Mets are hot, I like Mahle's outlook if you're in need of innings.

Cal Quantrill, Texas Rangers @ Los Angeles Angels

The Angels might be our favorite target right now, ranking in the bottom 10 essentially across the board in offensive box stats and striking out as much as any team in the league. It's even better when looking just at the past month, as LA is clearly in the bottom five and has scored by far the fewest runs in that time. There's not a whole lot to add; the Angels are a team to attack every day with opposing pitchers.

Quantrill has worked out of the bullpen more often than he has started this season, beginning seven games versus 17 relief appearances. His numbers are all average or better aside from his strikeout rate, which is far below average. He has pretty much always been a below-average K pitcher, but his current rate of 15.6% would be the second worst of his career if it holds. Every pitcher strikes out fewer batters when starting rather than pitching in relief, so it doesn't bode well for Quantrill that most of his outings have been out of the bullpen.

Quantrill is a low-to-mid-level streamer. Stats can be a little deceiving for relievers, especially a guy who has just 65 2/3 innings on the season, but Quantrill has been good enough to consider with such a great matchup (just don't expect a big ceiling).

Will Warren, New York Yankees vs. Seattle Mariners

Warren's teammate Ryan Weathers was listed here yesterday under similar circumstances: a pitcher who is owned in around 50% of leagues, making him a fringe streamer, but who has enough availability to make it worth checking on him, especially considering the fantastic matchup. Weathers allowed just two hits and one run in 5 2/3 innings, though three walks weren't great (to go with four strikeouts). Warren is a little better than average with both walks and strikeouts and has been right around the middle this year allowing hits, runs, and homers. He's worthy of a spot in about every league today considering his matchup.

Seattle has been one of the worst offensive teams in the league, ranking last in runs and in the bottom 10 in essentially every box stat. They hit for some power, but even their home run total has fallen to an average level; there's just nothing that the Mariners are really doing to put fear into opposing pitchers, and it's costing them ground in a very winnable division, as Seattle has lost six of their past seven games with just nine total runs in that time.

Warren is a mid-to-high-level streamer. He has been good in about every area, and his above-average strikeout work gives him a nice ceiling, especially against a Seattle team that strikes out near a top-10 level.

Wednesday's Streamer Rankings

1. Will Warren, NYY
2. Tyler Mahle, ATL
3. Cal Quantrill, TEX
4. Luis Castillo, CWS