SAN DIEGO -- Starting pitcher Ryan Weathers exited the Padres’ 3-1 loss to the Rockies on Sunday afternoon with a left leg injury after a collision up the first-base line in the top of the third inning.

Weathers, a 21-year-old rookie who has been a hugely important contributor for San Diego during the first half, fielded Jon Gray's bunt and attempted to tag the Rockies’ pitcher as he headed for first base. But Weathers planted his right leg awkwardly, and immediately went to the ground, losing the ball and his glove upon contact with Gray.

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Initial concerns centered around both Weathers’ right knee and foot area. He was evaluated by team doctors, who came away confident in Weathers’ knee, structurally. But he was sent for further tests on the back of his foot in the area of his Achilles, manager Jayce Tingler said.

“He’s walking around much better than when he came off the field,” Tingler said. “But he still can’t put a lot of weight on it.”

After the collision, Weathers was down for several moments as he was evaluated by the Padres' medical staff. The left-hander walked gingerly off the field and was replaced by right-hander Pierce Johnson.

Weathers has a 2.91 ERA this season in 17 appearances -- 11 of them starts. He had served as a useful swingman between the rotation and bullpen and -- despite innings limitations -- figured to play a crucial role on the Padres’ pitching staff down the stretch.

Even before Weathers went down, the Padres were in search of starting pitching help ahead of the July 30 Trade Deadline. If Weathers were to miss significant time, it would only serve to reinforce that need.