Skenes' Fastball Elevation Is Feeding Home Run Spikes—and the Market Hasn't Fully Priced It

Paul Skenes takes the ball Thursday night at PNC Park still commanding the majors' lowest WHIP at 0.82, a pace that would rank among the best full-season marks in a decade. But beneath that elite overall number sits a concrete mechanical deterioration: the Pirates' ace is allowing 0.90 home runs per nine innings, a 53% spike from his 0.59 career rate entering 2026. Four of his six homers allowed have come off fastballs, and the source of that vulnerability is deliberate—Skenes is elevating fastballs in the zone 20% more frequently than last season.

This isn't random variance or bad luck. Skenes threw consecutive starts with three-plus earned runs for the first time in his career, capped by a nine-hit, four-run outing in Toronto on Saturday where he completed five innings with fewer than five strikeouts—only the fifth time that's happened in his MLB career. His own postgame commentary centered on pitch execution and getting ahead in counts, diagnostic signals that he's working through a mechanical adjustment, not playing through injury. The Cy Young betting market read it the same way: Skenes dropped from +190 to +450 as a repeat winner in less than a week.

Historically, Skenes has shown resilience after back-to-back losses. In early May, he dropped consecutive starts against the Cubs and Cardinals before avoiding a three-game skid with six strong innings at the Mets in a no-decision. But this week's matchup carries asymmetrical risk. The Cubs snapped a 10-game losing streak Wednesday with a 10-4 demolition that included a tiebreaking three-run homer from Ian Happ—offensive violence after an extended drought. Chicago is now one of only two teams in history (alongside 2017's Dodgers) to string together two 10-game winning streaks AND a 10-game losing skid in the same season, a profile that suggests a volatile, recalibrating lineup capable of exploiting pitcher vulnerability when it appears.

Skenes has never faced the Cubs this season and carries a 2-2 record with a 2.94 ERA across seven career starts against them. The SportsLine projection model expects 5.5 innings, 1.7 earned runs, and 6.5 strikeouts—modest volume for a Cy Young-caliber starter. The market has Skenes at +130 to win personally and posted his strikeout total at 6.5. The fastball elevation mechanic explains why unders on strikeout volume and overs on home-run exposure have real texture here. When a pitcher elevates more, he induces more contact and fewer whiffs; when that elevated fastball catches the zone, it gets hit hard. The Cubs' recent offensive activation—especially after weeks of RISP futility—creates a narrow window where this specific mechanical vulnerability meets a lineup that just proved it can capitalize on loose strikes.