Perhaps it's time to stop trying to figure out how the Red Sox are doing this. Because you won't have much luck.

Mike Carp's game-winning grand slam in the 10th inning Wednesday night was the seventh pinch-hit home run of the season for the Sox. No other American League team has more than four. The Sox are tied with the Nationals for the most in baseball.

Carp was designated for assignment just before spring training by the Seattle Mariners the team with the third-worst offense in the American League. The Red Sox picked him up for what amounts to loose change.

In 211 plate appearances Carp is hitting .314 with a .938 OPS. He has nine home runs and 37 RBIs. Of his 59 hits 27 have been for extra bases. Few players have done more with their opportunities than Carp has.

Wednesday was Carp's crowning moment.

"To sit there for nearly four hours and come up and swing at the first pitch you see for a grand slam is pretty remarkable" John Farrell said.

When the Rays called in righthander Roberto Hernandez with two on Farrell told Carp to get ready to pinch hit for Johnny Gomes who was 0 for 8 in his career against Hernandez.

Hernandez walked Mike Napoli to load the bases. Carp came up swung at the first pitch he saw and drilled it out to center.

"Get a run in" Carp said. "I was looking for something out over the plate that I could put a good swing on and he hung a slider. I ended up doing a lot of more than I expected to do with it."