The Mets placed d'Arnaud on the 10-day disabled list Wednesday and recalled catcher Tomas Nido from Double-A Birmingham in a corresponding roster move.
D'Arnaud underwent an MRI and other tests at the Hospital for Special Surgery in New York. D'Arnaud has not yet decided whether to have the surgery.
"The doctors obviously will have conversations with Travis, and then Travis has to make that tough decision," Mets manager Mickey Callaway said. "That's a long road if he goes the surgery route."
It is not clear when d'Arnaud suffered the injury to his throwing elbow.
His replacement, Kevin Plawecki, was hit by a pitch on the left hand in the eighth inning Wednesday against the Marlins and left the game. The Mets breathed a sigh of relief when X-rays were negative, and are hopeful Plawecki won't be sidelined for long. He figures to see the bulk of the playing time in his absence, with Nido serving as a backup.
"That's a big one," Callaway said. "I was worried about that the rest of the game once he came out. To lose two catchers would be tough."'
Plawecki was "pretty sore," Callaway said, and might miss some playing time.
D'Arnaud, 29, has struggled with injuries throughout his six-year career. He played in a career-high 112 games last season and hit 16 home runs, also a career-best. D'Arnaud has three hits, including a homer, in 15 at-bats this season.
Information from The Associated Press was included in this report.