Starting Pitcher Fantasy Baseball Breakouts or Fake Outs? Pitchers On The Rise (Week 4)

April 23, 2026

Are these pitchers fantasy baseball breakouts or fake outs? Dan analyzes advanced pitcher statistics and surging fantasy baseball SPs for Week 4 of 2026, including Will Warren, Chase Dollander, and Peter Lambert.

Every week, the pitchers I chose to analyze in this article change from the time I start to plan it out to when I actually sit down to write it. Case in point, I was going to write about the rather boring Justin Wrobleski in this feature today, but ditched him at the last minute to dig into a much more compelling pick-up, Peter Lambert, after he shoved against the Guardians yesterday. We have to discuss the possible breakout of Colorado's second-year stud, Chase Dollander, too. And to round it out, we'll examine Will Warren's start to the season to see what he's doing differently this year as he's making his case to stick in the rotation even after Gerrit Cole and Carlos Rodon return.

If you are new to this column, remember that the goal is to look at several pitchers each week who are showing signs of "breaking out." That term gets thrown a lot in our industry, but for me, it simply means they're flirting with the possibility of improving their baseline performance over a larger sample size.

So, while we typically look at younger pitchers as potential "breakouts," I won't limit myself to only youngsters. The concept of the breakout can be applied to pitchers of all experience levels, as we have seen numerous examples of pitchers improving in a big way from season to season, even into their thirties. All rostership percentages are courtesy of Yahoo! Let's see which of these arms we can trust going forward, and also where to expect regression in the future!

Will Warren, New York Yankees

• 64% Rostered
• 2025 stats: 9 W, 162.1 IP, 4.44 ERA, 1.37 WHIP, 24.1% K%, 9.1% BB%
• 2026 stats: 2 W, 25.1 IP, 2.49 ERA, 1.07 WHIP, 29.5% K%, 5.7% BB%

The Yankees have an embarrassment of riches right now in their rotation. I am not sure they could have dreamt up a better start to their season than having Cam Schlittler dominate like an ace, while both Ryan Weathers and Will Warren have been fantastic in their own right. Heck, even Luis Gil turned in a scoreless outing in his most recent start, while Max Fried is doing his usual thing, providing steady innings from the top of the rotation.

Warren's 2025 campaign was pretty solid overall, but marred by inconsistency as he tended to run hot and cold for stretches. He finished with an ERA of 4.44 and a WHIP of 1.37, which certainly didn't help your ratios, but he did eat innings and stacked up over a strikeout per frame.

So far this year, we've only seen the good version of Warren, as he's allowed two earned runs or fewer in all five of his starts. Going into his last start, the only complaint might be that he simply wasn't pitching deep enough into games to qualify for a win, making it into the sixth inning just once.

But then he turned in a dominant performance against the Royals, striking out 11 over seven solid frames.

11 punchouts for Will Warren!

He matches his career high in strikeouts across 7 strong innings 💪

(MLB x @Abbvie) pic.twitter.com/0BLFFjfUug

— MLB (@MLB) April 18, 2026

So is that outing a sign that Warren is indeed emerging as a serious asset in fantasy baseball? Can we trust him as a guy that we start every time out now, regardless of opponent?

So not much has changed with Warren's arsenal; he's still featuring his fastball, sinker, and sweeper the majority of the time. Warren has excellent movement on his sinker, sweeper, and changeup (a pitch he could probably feature more).

He's not quite the magician that Nolan McLean is with these spin rates, but it's easy to see why his K% is outperforming his SwStr% (9.4%) as the movement on his pitches catches hitters looking (31.7% of all his strikes and called strikes).

So while the increase in strikeouts is probably not likely to stick (Warren's SwStr% is nearly identical to last year), he has shown that he can still stick in that 24-25% range that often yields around a K per inning.

One of the biggest improvements appears to be his command. He's cut his walk rate down by 3.4% to a really solid 5.7%, backed by a 1.7% drop in his Ball%. If that sticks, it would be a huge boon to his WHIP, which he's trimmed by 0.26 from last year.

The other development here is that Warren's raised his GB% to 50.7%, the best rate of his MLB career thus far. He had great ground ball rates in the minors, so it's good to see him finally inducing more ground balls at the MLB level at a high rate. It's ultimately going to help him pitch deeper into games if he can get some easy groundball outs. He's throwing his sinker about 5% more often this year, which could be part of the reason we are seeing ground balls, but it's also likely a product of throwing more strikes in general, getting ahead of hitters, and hitting his spots with better location and more consistency.

There are no real red flags here; the BABIP, HR/FB, and strand rates all look normal.

Verdict: The ERA indicators all suggest only minor regression, and Warren's improved control is a potential major development. Even if his strikeout rate returns to where it was last year, we are looking at a very valuable starting pitcher for fantasy purposes, and it's looking like his spot in the Yankees rotation could be solidified, with Luis Gil being the first pitcher to be moved to the bullpen when Cole or Rodon return. It's a mini-breakout, but it surely seems real to me!

Chase Dollander, Colorado Rockies

• 12% Rostered
• 2025 stats: 2 W, 98 IP, 6.52 ERA, 1.55 WHIP, 18.6% K%, 11.1% BB%
• 2026 stats: 2 W, 25 IP, 2.88 ERA, 1.00 WHIP, 30.8% K%, 6.7% BB%

So let's just clear this up right away. Yes, Chase Dollander is a starting pitcher. No, he has not started a game this season. The Rockies have been using an opener ahead of him, but he's gone five to six innings in his last two appearances, striking out nine batters in each, and has already matched his win total from the entire 2025 season!

Dollander is a former first-round pick in 2023 and was fast-tracked to the major leagues. He threw only 118 innings in 2024 across three levels of the minors, and made only four starts at Triple-A last season, making his other 21 starts for the Rockies.

So whether Colorado is trying to manage Dollander's innings with this piggyback role, or just trying to help him avoid the top of the lineup for a third time, it's definitely working. He looks like an entirely different pitcher this season and much more closely resembles a star prospect than he did last year.

Chase Dollander, K'ing the Side in the 4th. pic.twitter.com/J3n992IHhU

— Rob Friedman (@PitchingNinja) April 22, 2026

So what's been the big difference? Well, let's start with the fact that he's now averaging 99 mph on his heater, up a full tick on the radar gun from last season. Because he throws from a low arm angle (24 degrees), he gets a lot of "ride" or horizontal movement on it, rather than the induced vertical break that we typically see from pitchers with a higher arm slot. It's more of a Paul Skenes fastball than a Ryan Pepiot fastball.

But the fastball is generating a 30% whiff rate, compared to just 19% last season, and has seen a major improvement in batted ball results. Last year, his fastball was getting crushed often, even though he was throwing it hard.

He's also lowered his fastball usage considerably, while doubling his sinker usage and adding a sweeper (which still seems like a work in progress). Every pitcher, besides the sinker, is getting whiffs at a 29% rate or higher, and he's...wait for it...throwing a lot more strikes, too!

Groundbreaking revelation here, but throwing more strikes and cutting down on walks is a pathway to improving just about every aspect of your stat line. Dollander has trimmed his walk rate from 11.1% to 6.7%, which is backed by a borderline elite Ball% of 33.4%. That 5% reduction in Ball% is massive and a great leading indicator of continued improved control.

Last, but not least, there is the whole Coors Field thing to address. Yes, he's made three of his five appearances on the road to start the year, but his most recent dominant outing came at home against a pretty good Padres lineup. While the park factor is less than ideal, the improved strikeout stuff and ground ball rate (52.5% - up 10% from last year) are going to go a long way towards helping him keep that ERA down.

Verdict: All the advanced stats seem to support what Dollander has done so far. I think he's easily one of the best pickups on the wire right now, and whether he starts games or continues to pitch in relief matters very little to me. This is a major prospect who suffered through a terrible rookie campaign, but is clearly learning how to pitch. He has the stuff to dominate, and it should be fun to watch him continue to develop this season.

Peter Lambert, Houston Astros

• 3% Rostered
• 2024 stats: 2 W, 61.1 IP, 5.72 ERA, 1.66 WHIP, 17.9% K%, 10.4% BB%
• 2026 stats: 1 W, 11 IP, 3.27 ERA, 1.27 WHIP, 33.3% K%, 8.3% BB%

So we go from the current Rockies' ace to a former Rockies' farmhand who might be finding new life in Houston. I mean, where the heck did Peter Lambert come from, and how has he struck out 16 hitters over his first two starts (33% K%, 17.7% SwStr%)?

Lambert was a second-round pick of Colorado all the way back in 2015 as an 18-year-old and spent the first 10 years of his career in the Rockies organization. He made 35 starts over four seasons with Colorado and had a career ERA over 6.00.

Last year, he went to Japan and made 21 starts for the Yakult Swallows. But unlike someone like Cody Ponce, who had great success overseas before returning to the states, Lambert was 3-11 in his lone season in the NPB with a 4.26 ERA and 1.50 WHIP.

So I am not sure what Houston saw in him, but they may have discovered another diamond in the rough, as Lambert has turned in two impressive starts for the Astros since activating him from Triple-A after only two starts there.

Peter Lambert's 7th and 8th Ks. pic.twitter.com/EWVRa7Lh7u

— Rob Friedman (@PitchingNinja) April 22, 2026

So the whiffs and strikeouts are a pretty great development for Lambert, but without any type of track record of doing this in the past, they're not likely to stick over a larger sample size. It's a very interesting six-pitch arsenal for Lambert, with his slider and slurve both looking like his best pitches in terms of movement.

His fastball is sitting at 95 mph, which is solid, but also right around the league average. It has solid iVB (17 inches) as Lambert throws out of a high arm slot, which at that velocity is going to be pretty effective. It's pretty odd to see a guy go with a cutter, slider, and slurve all in the same mix, but it does give him three different breaking pitches that are all at distinctly different velocities.

A 52% GB% is a great sign, but not something he's ever sustained before, so we have to be pretty careful here with the super small sample size. He's missing bats, though, and not getting barreled up (just 7.7%). His xERA is 4.95, which does signal that he is giving up some hard contact, but his SIERA is just 2.68, likely because of the high K% and GB%.

So can a pitcher who has been, without mincing words here, pretty darn bad for his entire career, all of a sudden be good? We have seen it happen before, so anything is possible, and there's not too much evidence here of a total fakeout. Where he settles after a few more starts is probably somewhere between his baseline and his first couple starts; at least some regression seems likely.

Verdict: There is little to no risk in adding Lambert as a speculative pickup if you have a free roster spot. I don't think he'll continue to be this effective as a strikeout pitcher going forward, but there's enough to like in his profile that warrants adding him in the short term. We could be getting faked out here, for sure, but I'm curious enough to risk being burned if he completely melts down the next couple of times out.

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