TORONTO -- Roger Bernadina was forced to leave Monday's contest against the Blue Jays in the fourth inning after straining his right hamstring going from first to third base.

Blue Jays reliever Chad Beck, who entered in the first inning after starter Brandon Morrow exited with a left oblique strain, threw a wild pitch on a 1-2 count that darted to the right of catcher J.P. Arencibia.

Bernadina, who was on first after drawing a one-out walk, made it all the way to third but was in obvious agony after getting to his feet after the headfirst slide. The center fielder favored his right leg and was removed after being tended to by the Nationals' training staff and manager Davey Johnson.

Xavier Nady entered as his replacement and was shifted to right field in the bottom half of the inning, with Bryce Harper moving over to center.