ATLANTA -- New York Mets first baseman Pete Alonso returned to New York for further testing Thursday after being hit on his left wrist by a pitch and leaving Wednesday night's game against the Atlanta Braves.

Manager Buck Showalter said Alonso had a CT scan in Atlanta on Thursday morning. The slugger was scheduled for an MRI later Thursday in New York.

Asked why the additional testing was taking place in New York, Showalter said, "I think we'd rather have our people look at it."

Alonso, who leads the majors with 22 homers, was hit by a 96 mph fastball from Charlie Morton in the first inning of Atlanta's 7-5 win Wednesday night.

The Mets said Wednesday night that Alonso had a contusion and X-rays revealed no broken bones. More tests were scheduled even before Showalter said Alonso had more soreness in the wrist Thursday morning.

"We had plans for him to have the scan this morning anyway, just to be on the safe side," Showalter said.

Following Wednesday night's game, Morton apologized to Alonso, one night after Alonso hit a long homer and then was heard yelling to Braves right-hander Bryce Elder, "Throw it again. Throw it again, please. Throw it again."

"He was looking for me," said Alonso of Morton's postgame visit Wednesday night. "He just wanted to apologize. Obviously he didn't mean to. For people speculating for this or that, I just wanted to clear that. Chuckie's a good guy and the situation didn't call for it either. There's nothing to it. I just happened to get hit with an up-and-in fastball."

The Mets entered Thursday night's game on a five-game skid and played without Alonso for the first time this season.

A serious injury to the slugger would be damaging to the Mets' hopes of getting back into contention in the NL East. New York entered Thursday's game in third place, 7½ games behind Atlanta. Showalter said he remained optimistic Alonso can return during a three-game series at Pittsburgh that begins Friday.

Alonso leads the NL with 49 RBIs and is hitting .231.

Rookie Mark Vientos, recalled from Triple-A Syracuse on May 17, made his first start of the season at first base as a fill-in for Alonso, who has 59 starts at first and three at designated hitter.