"It's been pretty good," said Padres manager Bud Black. "We have a couple of guys that can do it. When you have those guys, the other team worries about it. Power is a weapon, power is real."
Grandal, Seth Smith (March 30 against the Dodgers), Alexi Amarista (April 6, Marlins) and Xavier Nady (April 13, Tigers) are the others to come off the bench and go deep this season.
The four pinch-hit home runs are the most in the Major Leagues this season. The second-place Pirates have done it twice. The only Major League team to have more pinch-hit home runs through the first 17 games of the season was the 2001 D-backs with five in 17 games.
"Going back [to days as a player], I'm remembering certain guys on that bench that might pinch-hit, if there's a threat of a homer or damage, it's disconcerting," Black said. "In most cases when a guy pinch-hits, the game is in the balance. One swing of the bat can change the complexion of the game."
Corey Brock is a reporter for MLB.com. Keep track of @FollowThePadres on Twitter. This story was not subject to the approval of Major League Baseball or its clubs.