Michael Conforto receives congratulations from Eric Campbell after Conforto scored...

 Michael Conforto receives congratulations from Eric Campbell after Conforto scored a run in the fourth inning against the Washington Nationals in a spring training baseball game, Thursday, March 3, 2016, in Viera, Fla. (AP Photo/John Raoux) Credit: AP / John Raoux

DUNEDIN, Fla. — Mets leftfielder Michael Conforto will be examined by doctors after leaving Wednesday’s 2-1 loss to the Blue Jays with stiffness in his lower back.

Conforto left after his second at-bat, a strike out in the fourth inning. He felt the stiffness after making a swing earlier in the plate appearance.

“It’s just a little bit frustrating just because I can’t remember the last time I came out of a game,” said Conforto, who is hitting .222 in the spring after going 0-for-2. “But I’ve been relatively pain free.”

Mets manager Terry Collins said Conforto has had back spasms in the past.

Conforto was among a contingent of Mets to take the early-morning bus ride from Port St. Lucie to Dunedin, a three-hour trek that he said left little time to loosen his back before the game.

“I think it was just a weird day,” Conforto said. “It was an early bus ride, we got here a little bit late, I didn’t get to swing in the cage before I went out on the field. So, I think with a little preparation, a little treatment, I’ll be fine in a few days.”

Harvey’s tune-up

Matt Harvey makes his third Grapefruit League start in a split squad game against the Astros on Thursday. Harvey will be opposed by AL Cy Young Award winner Dallas Keuchel.

Harvey’s last game appearance was scratched because of looming bad weather. He instead pitched in a minor-league game.

In the other split-squad game on Thursday, Logan Verrett starts for the Mets against Joe Kelly and the Red Sox in Fort Myers.