With half of the season still to come, time remains to make history. According to Baseball-Reference, since 1973 -- the earliest season for which complete data is available -- the most walk-off grand slams in a season was eight in 2002. There were seven walk-off grand slams in 2008.
Monday marked the end of the season's third full month and upped the 2014 total to five. Here is how things have reached this point, with the summer months waiting ahead.
June 30: Tigers 5, Athletics 4
Trailing by three runs and with one out, Tigers left fielder Rajai Davis hit the second pitch from the A's Sean Doolittle, a curveball left over the plate, and sent it over the left-field fence for a walk-off grand slam at Comerica Park.
The walk-off grand slam was the first with a team down by exactly three runs since Arizona's Ryan Roberts did the same on Sept. 27, 2011, against the Dodgers. It was the eighth walk-off grand slam in Tigers history since 1938.
June 19: Indians 5, Angels 3
After the Angels took a 3-1 lead in the top of the 10th in Cleveland, Indians designated hitter Nick Swisher batted with two outs and the bases loaded against Ernesto Frieri. Down 1-2 in the count, Swisher drove a fastball over the right-field fence.
The walk-off grand slam was the first for the Tribe since Travis Hafner's game-winning shot against the Blue Jays on July 7, 2011.
April 25: White Sox 9, Rays 6
Jose Abreu may have been in his first month in the Majors, but the pressure proved not to get to him when he batted with the bases loaded and the White Sox trailing by one in the ninth. Abreu sent a fastball from the Rays' Grant Balfour over the right-field fence to secure a walk-off victory.
The grand slam was Abreu's ninth home run in the month of April, the most in the month by a rookie in Major League history, surpassing the eight Pujols hit in April 2001. Carlos Delgado and Kent Hrbek also hit eight homers in April as rookies.
April 18: Marlins 8, Mariners 4
Tied at 4 with the bases loaded and no outs, the Marlins' Giancarlo Stanton drilled a 1-2 curveball from Yoervis Medina 407 feet over the wall in left-center field.
It was Stanton's second career walk-off slam, with the first coming on May 13, 2012, against the Mets. Miami has had five walk-off slams all-time, with the last by Jeff Mathis on June 30, 2013.
April 5: Mets 6, Reds 3
What a way for the first home run of a season to come. Trailing by one, the Mets' Ike Davis sent a curveball from J.J. Hoover over the right-field fence for a walk-off grand slam and the Mets' second win of a young season.
Since 2000, this was the earliest walk-off grand slam in a season.
• No player knows the grand slam better than Alex Rodriguez. Of his 654 career home runs, 24 have been grand slams, the most by any player in Major League history. Only two other players have hit more than 20: Lou Gehrig (23) and Manny Ramirez (21).
• Two players have hit six grand slams in a single season: Hafner (2006) with the Indians and the Yankees' Don Mattingly (1987).
• Only one player has hit two grand slams in an inning -- the Cardinals' Fernando Tatis, at Dodger Stadium on April 23, 1999. Both were off Chan Ho Park in the third inning.
• Four players have hit three career grand slams in their careers as a pinch-hitter: Ben Broussard, Rich Reese, Willie McCovey and Ron Northey.
• The most grand slams by a team in a single season is 14. The Indians did that in 2006 with the help of Hafner's six, and the A's did it in 2000.