PHILADELPHIA — After a rainout in Syracuse, Blade Tidwell was finished for the day.

He was about to begin playing some “Fortnite” on Thursday night when his plans changed.

The pitching-desperate Mets burned Justin Hagenman’s arm in relief in their finale in Atlanta.

So at about 10 p.m., Tidwell was told he was starting Friday.

To make roster space for Tidwell, the Mets optioned Hagenman

“Just got into the car,” Tidwell mentioned as he and his girlfriend embarked on a 4 ½-hour journey south in preparation for facing one of the top offenses in baseball.

Tidwell was better, if not excellent, in an emergency spot start during a 10-2, series-opening loss to the Phillies at Citizens Bank Park.

After a May 4 debut in St. Louis went wayward — six runs in 3 ²/₃ innings — the 24-year-old prospect held his own over three scoreless innings.

He ran into trouble in a fourth inning he would not escape, perhaps a victim of circumstance.

For the first time all season, he was starting consecutive games on four days’ rest. He typically gets at least five days’ rest with Syracuse.

In his outing Sunday, he had thrown just 66 pitches. For that reason, manager Carlos Mendoza did not want to give him much of a leash.

In the fourth inning, singles by Nick Castellanos and J.T. Realmuto and a walk to Bryson Stott loaded the bases.

Tidwell managed to get Otto Kemp to hit a ground ball, but the defense comprising Brett Baty, Jeff McNeil, and Pete Alonso was slightly slow in executing the play, resulting in the game’s first run being scored.

With 74 pitches thrown, the right-handed pitcher was substituted after giving up four hits and three walks, while also securing four strikeouts. Jose Castillo took over but allowed another run to cross the plate.

“I thought the fastball had life. I thought the cutter, shorter slider, to go with the sweeper, was a lot better, as well,” Mendoza said.

Tidwell added: “It went better than the last, but there’s still work to be done.”