Bay, 33, dove into the warning track last night as he tried to catch Jay Bruce’s inside-the-park home run in the second inning. His head hit the lower part of the wall.
The outfielder had difficulty getting up and finding the ball. His throw failed to reach home plate before Bruce crossed for the score. Trainer Ray Ramirez escorted him off the field.
Bay missed the last two months of the 2010 season with a severe concussion received when he struck the left-field wall at Dodgers Stadium.
This season, Bay was on the disabled list from April 24 to June 6 with a fractured left rib.
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