NEW YORK -- When Mets shortstop Ruben Tejada first stumbled to the ground, manager Terry Collins thought he was simply embarrassed about tripping over his spikes. Then the scene grew more sinister, as Tejada lay motionless for several moments in the dirt beyond the first-base bag.

After some deliberation, the Mets determined that Tejada had strained his right quad; after he walked off the field under his own power, the Mets sent him to the hospital Sunday evening for an MRI, which should reveal the severity of the injury. Tejada also suffered several cuts and bruises on his face, which took such a beating that Collins thought his eye might swell shut.

First-base coach Tom Goodwin, who watched the play unfold, believes Tejada was caught between sliding into first base and pulling up to stop his momentum. Tejada, who was attempting to beat out a bunt single on the play, was at the Hospital for Special Surgery in Manhattan after Sunday's game and unavailable for comment.

"He had pretty good momentum going forward," Goodwin said. "So when he hit ... there was nothing to break his fall."

"When he picked his head up and I saw his eye, I said, 'Ooh,'" Collins said.

Without knowing the shortstop's MRI results, Collins said he believed this injury was not as bad as the groin strain that sidelined Tejada for nine days in Spring Training. If Tejada is out for only a brief period of time, the Mets are willing to proceed with Justin Turner at shortstop and David Wright as his emergency backup.

But the team is nonetheless planning to fly a middle infielder -- likely Jordany Valdespin -- in to meet them in Philadelphia as part of Major League Baseball's taxi squad provision. Though the Mets optioned Valdespin to Triple-A Buffalo on Saturday, MLB rules stipulate that they can reactivate him if they place Tejada on the disabled list.

One alternative would be calling up Omar Quintanilla, who has been serving as Buffalo's everyday shortstop. Or the Mets could simply wait for Ronny Cedeno, who has been on the disabled list since April 21 with a left intercostal strain. Cedeno will begin a Minor League rehab assignment Monday, with the Mets planning to activate him Friday. So if the injury to Tejada is not serious, they may simply play shorthanded for four days while they wait for Cedeno.

Mostly, the Mets are concerned about losing Tejada right as he was beginning to hit his stride. The shortstop was 2-for-2 Sunday, elevating his average to .421 over his last nine games. He is hitting .305 overall this season, with his .362 on-base percentage, third on the team behind David Wright and Kirk Nieuwenhuis.