NEW YORK — Mets first baseman Pete Alonso watched in disbelief as starter Kodai Senga fell to the ground holding on to his hamstring.

Alonso delivered a high-throw to first base on Thursday, causing Senga to jump for the ball. In the play, Senga strained his hamstring and is headed to the injured list. After the game, Alonso addressed the play and said he feels awful.

The Mets got good news on Kodai Senga. The right-hander was diagnosed with a Grade 1 strain in his right hamstring — the lowest level of severity — and is expected to be re-evaluated before the end of the month, manager Carlos Mendoza said.