What happened: Juan Soto departed before the top of the fifth inning Tuesday night with what the Mets called left-side back tightness, and manager Carlos Mendoza said the left fielder is day to day after his back locked up. Jared Young shifted from first base to left to replace him, with Mark Vientos moving to first. The exit came on a night Kodai Senga allowed seven runs in 3 2/3 innings in his second start back from the injured list. This continues the storyline from when Soto first left the game early with left-side back tightness.

Why it matters: Soto had entered Tuesday leading New York in most offensive categories with a .974 OPS, trailing only the Dodgers' Shohei Ohtani in the National League, so any absence cuts deep into an already-thin lineup. Mendoza said he would speak with president of baseball operations David Stearns about Senga's rotation status, with Stearns having signaled that performance must improve. The timing stings as Francisco Lindor nears a return from a left calf strain that has sidelined him since April.

What to watch: Christian Scott is expected back from the injured list this weekend, while Stearns said the rotation will be evaluated turn by turn. Watch whether Soto avoids the IL and whether Senga keeps his spot for his next scheduled start.