Padres rookie Fernando Tatis Jr. is “most likely done for the season.” because of a back injury, San Diego mananger Andy Green told reporters on Friday.

The injury makes Pete Alonso’s road to the NL Rookie of the Year award a little clearer as Tatis was the Mets first baseman’s chief competition.

Tatis, who had been dealing with a back issue, was placed on the 10-day injured list retroactive to Wednesday when he appeared to tweak his back on a swing. The shortstop is hitting .317 with a .969 OPS, 22 home runs, 53 RBIs and 16 stolen bases this season and has been dazzling on defense. The Padres entered Friday 7 ½ games out of a wild-card spot.

Alonso tied Cody Bellinger’s National League rookie record for home runs in a season at 39, with this blast against the Braves on Thursday night. He is hitting .264 with 91 RBIs and a .965 OPS to help the Mets climb within two games of the second wild-card spot.

Alonso’s competition for the award also includes Mike Soroka (Braves), Alex Verdugo (Dodgers) and Bryan Reynolds (Pirates).