Week 13 of the 2026 fantasy baseball season arrives with a fresh wave of waiver opportunities, especially at the starting pitcher position. In shallow leagues, the threshold sits under 40% rostered players, while deeper formats require a sub‑30% threshold. This creates a fertile ground for savvy managers to snag arms that are outperforming their draft status.
Shallow‑League Standouts
Michael McGreevy continues to impress for the St. Louis Cardinals, posting a 3.35 ERA and a 1.15 WHIP across 15 starts. His blend of a sharp fastball and a tight changeup has kept hitters off balance, making him a prime candidate for pickup in leagues where he remains under the radar. Alongside him, Kansas City’s Stephen Kolek boasts a 2.68 ERA and a 1.03 WHIP in eight starts, while Gage Jump of the Athletics has a 2.37 ERA and a 0.99 WHIP over five outings. Both pitchers are striking out batters at a healthy clip and should be on the radar for any manager seeking low‑cost upside.
Griffin Jax of the Tampa Bay Rays has shown a noticeable ERA dip since May, pairing it with an uptick in strikeouts that signals a maturing repertoire. Seth Lugo, also in Kansas City, carries a 3.69 ERA and a 1.35 WHIP in 11 starts, offering a reliable veteran presence that can eat innings and keep the bullpen fresh. These four arms collectively provide a compelling mix of cost‑effectiveness and performance for shallow formats.
Deep‑League Options
For deeper leagues, the talent pool stretches to include Peter Lambert of the Houston Astros, who sits at a 3.23 ERA and a 1.11 WHIP over 11 starts, and Walker Buehler of the San Diego Padres, posting a 3.96 ERA and a 1.32 WHIP across 13 starts. Andre Pallante (St. Louis) and Joey Cantillo (Cleveland) bring solid ERAs of 3.76 and 4.05 respectively, while Sean Burke (Chicago) and Sean Manaea (New York) round out the group. Manaea’s recent success after transitioning to an opener role has made him a versatile asset in most formats, especially when his matchup favors a high‑strikeout environment.
Beyond the highlighted names, a slew of lower‑rostered pitchers deserve attention. Kodai Senga, Brady Singer, Matthew Liberatore, Anthony Kay, Slade Cecconi, and Sam Aldegheri each bring a blend of youthful upside and proven durability. Their recent performances suggest they could become weekly starters if given consistent opportunities, making them valuable speculative adds for managers looking to future‑proof their rotations.
The strategic takeaway is clear: monitor ERA, WHIP, and strikeout rates, but also consider the context of roster percentages and upcoming matchups. The waiver wire remains a critical lever for fantasy success, especially when a handful of under‑the‑radar starters can shift the balance of power in a given week. By staying proactive and targeting the pitchers outlined above, managers can turn a modest pickup into a season‑long advantage.