WASHINGTON -- Evan Longoria left Monday's night's game for Triple-A Durham after feeling discomfort in his partially torn left hamstring.

The third baseman was playing in the second game of his rehab assignment with the Bulls when he felt soreness while running to first base on a groundout in the first inning, and he was lifted for a pinch-hitter in the third inning.

Longoria will join the Rays in Washington on Tuesday to continue his rehab under the watchful eyes of Tampa Bay trainers.

Longoria, who was hitting .329 with four home runs and 19 RBIs in 23 games before being injured on April 30, has no timetable for a return. The Rays want to take a cautious approach so that when he does come back, he will not have any setbacks.