On Monday, Felipe Lopez became the first player to homer from both sides of the plate on Opening Day in MLB history. An inning later, Lopez' teammate Tony Clark became the second. Needless to say, they were also the first set of teammates to homer from both sides of the plate on Opening Day in Major League history.
Just how rare a feat is this in general, though, ignoring the arbitrary Opening Day limitation? In Retrosheet's PBP files, which date back to 1954 and cover nearly 85,000 games, only one other pair teammates has accomplished this feat: Jorge Posada and Bernie Williams on April 23, 2000. That wasn't the only history Tony Clark was making, though.
In the Retrosheet era, Chili Davis and Eddie Murray hold the record for most times homering from both sides of the plate in the same game, each with 11 such games. Tied for third behind them with 10 each are Ken Caminiti, Mickey Mantle*, and, as of Monday, Tony Clark.
Some other interesting tidbits about players who have homered from both sides in one game (all figures since 1954):
-86 players have accomplished the feat a combined 227 times
-Nick Swisher has the most such games since 2000, with 7 in only 4 full years. He has had at least one such game every year since becoming a full-time Major Leaguer and has a total of 5 in the last 2 years.
-Felipe Lopez, while he has a 20 HR season on his resume, is not exactly known for his power. However, his 73 career HR are not even close to the fewest by anyone to accomplish the feat. Steve Jeltz, who homered from each side on June 8, 1989, has only 5 career home runs. Donnie Scott, Brian Simmons, and Rob Bowen have all also done it with single-digit career HR totals.
-If Lopez were to accomplish the feat again, his 75 (minimum) career HR would not even be close to the fewest by anyone with multiple such games. Burton Ellis did it on August 1, 1963 and then again in the first game of a doubleheader on September 7 the following year despite only hitting 17 career HR. Jeff Davanon (33 career HR), Jose Reyes (61), Melvin Nieves (63), and Mark Belhorn (69) have all done it twice with fewer career HR than Lopez as well. Dale Sveum did it 3 times with only 69 career home runs.
-The defensive position played most frequently by players to homer from both sides in the same game is center field, with 50 of the 227 games coming from center fielders. The only position to have never done it is pitcher. Next fewest is DH with 14 games, followed by second base and left field with 20 each.
-Ken Singleton's 246 HR make him the most prolific switch hitting slugger to never homer from both sides in the same game.
*Since Retrosheet's PBP files currently only go back to 1954 (and are missing a handful of games from the first couple decades the data is compiled for), this does not include the first few years of Mantle's career, so this might not be his complete total.