Which Phillies starter is being labeled as an early fantasy baseball sleeper pick?

All the fanbase mania revolving around a blockbuster Blake Snell, Jordan Montgomery, Shota Imanaga, or Yoshinobu Yamamoto signing this winter seemed to overlook the inconvenient fact that one of baseball's best rotations doesn't have the room.

While more pitching depth is always a good thing, adding a new frontline starter would have inevitably bumped emergent youngster Cristopher Sánchez, currently slated as the Philadelphia Phillies' five-man, from the picture. 

After very quietly posting outstanding numbers from the back of the rotation in 2023, a 3.44 ERA and 1.05 WHIP, Sánchez appears to finally be getting his due — not from Phillies fans or national media, though.

Sánchez receiving attention from the fantasy baseball community

The crafty lefty has been creeping his way up fantasy baseball draft boards this offseason, rising to an average draft position of 253.6 in the NFBC system. His pre-draft ranking as set by analysts, conversely, is well over 300 on most popular fantasy apps.

CBS analyst Scott White buys the hype, digging into Sánchez's late-season tweaks that resulted in the most dominant form of him we've seen at any professional level:

"Sanchez's 57 percent ground-ball rate would have ranked second among qualifiers, and his 4 percent walk rate would have ranked fourth," White writes. "By those measures alone, he would seem to be a useful Fantasy pitcher but then came the coup de grace in September. He began throwing his changeup more and became a genuine bat-misser as a result.

"The pitch had a 43 percent whiff rate for the year and gave him a 17 percent swinging-strike rate for the month. He struck out 10 in two of those starts, including one against the mighty Braves."

Until around midseason last year, Sánchez hadn't really given evaluators much of a reason to think he was more than a depth option. He had pitched to solid but unspectacular and fairly average numbers for a pitcher of his type throughout the minors, and had struggled to a 5.63 ERA across 15 games and three starts in 2022. It was easy to see the Phillies as a team with only four pitchers, and only three reliable ones with Taijuan Walker's struggles, as recently as last June or July. 

The changeup, indeed, was a difference maker.

But so too was giving him a consistent shot as a starter in the bigs. Sánchez came out of the pen to middling effect for much of 2022, and once he was allowed to settle into an every-fifth-day role in 2023, stepping into shoes that many believed would have been Andrew Painter's (or Bailey Falter's) in spring training, he thrived.

Still, Sánchez's full season of work in 2023 still hasn't been properly appreciated and should now more than reverse that perception. By measure of ERA+, Sánchez's 125 mark was actually the best on the entire Phillies staff in 2023, besting even Zack Wheeler's 119. At the very worst, he's one of the better fifth starters in the league. At best, he could emerge to be another potent playoff arm, behind Wheeler and Aaron Nola and alongside Ranger Suárez.

For fantasy purposes, the fact that he's obfuscated by the big, established names in the front of the Phillies rotation is a good thing. He'll likely continue to be underestimated in most formats, and given his low ranking, he could be an easy steal in the late rounds of drafts.

Will Sánchez pay off as a fantasy baseball sleeper?

It's fair to be skeptical about regression, particularly as Sánchez has only flashed this level of performance for one year. It should be noted that most projection systems expect regression from Sánchez. ZiPS (4.36 FIP) and Steamer (4.05) are bearish for 2024, and forecasts expect him to just barely meet his 2023 WAR of 1.8 despite throwing 35 or so innings more in 2024. 

Projection systems gave the Phillies miniscule chances of beating the Braves in the NLDS two years running too. And beyond the aforementioned improved strikeout rate, there are plenty of other reasons to be confident in Sánchez's staying power. 

Had he pitched enough innings to qualify, his xFIP (often a more reliable indicator than ERA) of 3.09 in 2023 would have been third in all of baseball. His batted ball exit velocity and barrel percentage numbers are average, but not low enough to indicate regression or any sort of glaring hole. His K/9 of 8.70 would have placed him 24th in all of baseball, just behind José Berrios and Cristian Javier. That's a good place for a "fifth" starter to be. 

Sánchez also averaged about 5 2/3 innings pitched per outing, solid metrics for a 26-year-old without injury history who can reasonably be expected to throw more in 2024. 

The Phillies still have not added meaningfully to their bullpen this offseason, and an addition to the rotation ahead of Sánchez seems unlikely. The team will inevitably rely on their top five to provide a lot of innings once again next season, limiting the space between the starter and the trusted arms like José Alvarado, Jeff Hoffman, and perhaps Orion Kerkering and Seranthony Domínguez.

Expect Sánchez to significantly increase his workload as he establishes his place in the rotation for years to come.