The primary driver here is the starter gap: Thornton's composite sits at 60.69 against Pérez's 28.92, a 32-point differential that reflects how far Pérez's ERA (3.38) has diverged from his FIP (4.54) — suggesting regression is lurking. Thornton's 1.93 ERA and 0.86 WHIP represent genuine early-season efficiency, and even with no xERA to anchor those numbers, the underlying WHIP gives confidence the surface results aren't purely luck. The Mets' lineup is a legitimate concern at 0.666 OPS vs. LHP and a 6-9 last-15 record, but the model's 58.8% win probability against a market-implied 48.5% produces a +10.3% edge that's worth acting on at 2.06. Atlanta's lineup composite (62.0) and 10-5 form are real counterweights, so this is a measured disagreement with the price, not a one-sided situation.