Center fielder Carlos Beltran left Thursday's game after the first inning with a right knee contusion suffered when he collided with Giants first baseman Rich Aurilia. He was replaced in the field by backup Carlos Gomez.
Beltran will have an MRI on the knee on Friday morning, and could potentially miss significant time pending the results of the exam.
"When it happened, I got scared," Beltran said. "I was in a lot of pain."
With one out in the first, Beltran hit a slow grounder toward second. A close play developed at first as Beltran, Aurilia and the ball all arrived at the same time.
"It was bang-bang," said manager Willie Randolph. "They kind of got tangled up for a second."
Second baseman Kevin Frandsen's throw wasn't close, sailing toward the Mets dugout. But in the chaos, Beltran and Aurilia collided. Trainers examined Beltran for several minutes before allowing him to stay in the game, and he later scored on a David Wright double -- an act that he said left him in extreme pain.
When the Mets came out on the field for the top of the second, Beltran was not among them. He went back to the clubhouse with significant swelling in the knee, and though the pain and swelling eventually subsided, Beltran said that the impact had sapped his knee of its strength.
"When I passed the bag, I felt like all the weight went to my right knee," he said, noting that he hoped to be back in the lineup soon. "It's better. It's weak, but it's better."
Beltran said that he had been playing with minor tendinitis in that knee for months. It's possible that the collision could have aggravated something, though results from Friday's MRI should provide a far more accurate indication.
Beltran had been batting .294 with eight home runs, playing in all 51 games for the Mets. But he had cooled off after a hot April, hitting just .226 in May.
If he's forced to sit -- and it seems overwhelmingly likely that he will be -- the entire outfield will be jammed with reserves. On Thursday it was the 21-year-old Gomez taking Beltran's place, joining Endy Chavez in right and Ben Johnson in left. None of those three was in the Opening Day lineup, and only one -- Chavez -- was even on the team.
There's no doubt that situation isn't ideal. Gomez started Thursday's game on the bench, in the middle of an 0-for-14 slide. He only added to that on Thursday, finishing hitless in three at-bats.
Yet at this point, the Mets are simply in search of healthy bodies. The team is now left without a primary backup outfielder, and would have to turn to an infielder -- namely Ruben Gotay or David Newhan -- should the need for a backup arise.
"We'll find somebody," Randolph said. "Hopefully, Carlos will be OK and it'll just be a little bruise or whatever, but we'll find a way."
The Mets had already placed starting corner outfielders Moises Alou and Shawn Green on the DL. Alou is likely due back sometime next week, and Green is set to return in mid-June.
Anthony DiComo is an associate reporter for MLB.com. This story was not subject to the approval of Major League Baseball or its clubs.