LOS ANGELES — Jacob deGrom is back to throwing from a mound.

In another significant step toward his return, the Mets ace threw a 19-pitch bullpen session Saturday in New York. It was deGrom’s first action off a mound since he was shut down during spring training with a stress reaction on his right scapula.

DeGrom, according to general manager Billy Eppler, threw all fastballs, with moderate intensity. He will continue his mound progression toward facing live hitters.

“Our assessments, in combination with Jake’s feedback, will drive that timeline,” Eppler said.

DeGrom last pitched for the Mets on July 7 2021, before he was placed on the injured list with forearm discomfort. He was later diagnosed with a low-grade tear of the ulnar collateral ligament in his right elbow. DeGrom appeared in two spring training games before the stress reaction on his scapula was diagnosed.

The Mets have been hopeful for a late-June or early-July return for deGrom, who is still relatively early in his “spring training” buildup.

“Obviously it’s mapped out, but plans are always tweaked when you go through them,” manager Buck Showalter said. “But he’s handled everything as well as we could expect. We’re comfortable with where he is right now.”