Arizona manager Torey Lovullo said it's too early to tell whether Mathis will miss the rest of the season. A 13-year major league veteran who is valued for his fine defense and leadership, Mathis was injured Monday night against the New York Mets when his bare hand was hit by a foul ball.
"We're going to miss him," Lovullo said.
Arizona began the night a half-game behind Colorado for the first National League wild card and 3½ ahead of Milwaukee for the league's final postseason berth.
In other moves, the Diamondbacks reinstated outfielder Reymond Fuentes from the 10-day DL and recalled right-hander Jake Barrett from Triple-A Reno to provide a fresh arm in the bullpen. Right-hander Jimmie Sherfy was optioned to Reno after pitching a perfect ninth inning Monday for his first major league win.
Fuentes had been sidelined since July 18 with a bruised left thumb.
Mathis has started 55 games this season while sharing catching duties with Chris Iannetta and Chris Herrmann. Mathis is batting just .213 with two homers and 11 RBIs but has thrown out 10 of 28 potential base stealers (35.7 percent), one of the top rates in the majors and by far the best on the team.
Iannetta was set to make his 49th start Tuesday night against the Mets. He was hitting .223 with 11 home runs, 29 RBIs and a .316 on-base percentage.
Herrmann was batting .158 with eight homers and 23 RBIs in 30 games, including 22 starts.
"We have two guys we feel really good about," Lovullo said. "It's time for them to step up. There's going to be some adjustments and we're going to continue to share information the way we have and do the things that we have done. These guys are ready for the challenge."
Lovullo said his plan right now is to play Iannetta three games out of every five, with Herrmann getting the other two.
Mathis, 34, got dinged in the fourth inning Monday night but remained in the game until the sixth.
"Just speaks volumes about his toughness and the example he sets," Lovullo said. "So we're going to continue to play hard for him and do what we're supposed to do to pick up the slack for him."
Mathis will see a hand specialist when the team returns home.
"Jeff's an extremely tough player. He's a tough man. So if there's one person that can come back on the low side of the timetable, it would be him. What that timetable is will be determined," Lovullo said. "At this point I've been told that surgery is not something that is a possibility. But obviously, we know things can change quickly."