Jacob deGrom of the Mets looks on against Atlanta at...

Jacob deGrom of the Mets looks on against Atlanta at Citi Field on Tuesday. Credit: Jim McIsaac

On the day the Mets traded for Javier Baez and activated Carlos Carrasco for his season debut, they also suffered a potentially crippling blow: Another setback for Jacob deGrom.

The Mets ace is dealing with elbow inflammation and has been shut down for at least two weeks, acting general manager Zack Scott said on Friday night.

DeGrom, who has been out since July 7 with what the Mets were calling forearm tightness, threw a 36-pitch bullpen session on Thursday. Scott said his last couple of pitches touched 98 miles per hour.

On Friday, deGrom didn’t feel right (once again) and had an MRI that Scott said (once again) showed no structural damage. Still, the Mets have (once again) shut down their ace and are now looking at a September return as a best-case scenario.

"We’re going to be careful and shut him down for a couple weeks," Scott said. "What we’ll do in a couple weeks is re-image and see if the inflammation’s gone away. If so, we’ll determine the next steps from there."

DeGrom is 7-2 with a 1.08 ERA in 15 starts and appeared well on his way to his third NL Cy Young award in four years before he started missing time with multiple physical ailments.

DeGrom has been out this season at various times because of right lat inflammation, right side tightness, right flexor tendinitis, right shoulder soreness and right forearm tightness.

Scott said nothing in particular triggered deGrom's elbow inflammation.

"This is standard stuff that happens with pitching," Scott said. "Sometimes normal wear and tear develops."

Scott said deGrom’s setback did not change his approach at Friday’s trade deadline.

"It didn’t change anything," he said. "You can’t replace Jacob deGrom."

The Mets are trying to hold off Atlanta and Philadelphia and Phillies in the NL East. On Friday, the Mets acquired Baez, the two-time All-Star shortstop, and righthander Trevor Williams from the Cubs. Williams, who was 4-2, 5.06 ERA in 13 games (12 starts) with Chicago, was sent to Triple-A Syracuse.

For now, the rotation consists of Marcus Stroman, slumping All-Star Taijuan Walker, 41-year-old lefthander Rich Hill, impressive rookie Tylor Megill and Carrasco, who made his first start as a Met on Friday after suffering a hamstring injury in spring training.

The Mets are also hoping Noah Syndergaard can give them some innings in September as he attempts to come back from Tommy John surgery.

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