As of 2017, under the Official Rules, how many unassisted triple plays have there been in MLB’s Modern Era?

The Modern Era began with the 1900 season. The first unassisted triple play (UTP) was by Shortstop Neal Ball of the Cleveland Naps in the second inning of the July 19, 1909 game against the Boston Red Sox.

Under MLB rules, when a ball is put into play, if the bases are loaded, each player on base must run to the next base. When a fielder catches the ball on the fly, the batter is out and all runners must return to his original base. Stepping on the nearest base puts out the runner running to that base. Tagging the runner returning to that same base completes the UTP.

Since that 1909 game, the UTP has been accomplished only 14 more times, the last by Philadelphia Phillies Second-baseman Eric Bruntlett in the ninth inning of the August 23 game against the New York Mets a century later, in 2009.

Eight UTPs were made by shortstops, five by second-basemen, and two by first-basemen. No pitcher, catcher, third-baseman, or outfielder has accomplished this feat.

Two players who were still active in 2017 each performed a UTP: Shortstop Troy Tulowitzki, of the Colorado Rockies, in 2007, and Second-baseman Asdrúbal Cabrera, of the Indians, in 2008. Bill Wambsganns, Indians second-baseman, is the only player with a post-season UTP, October 10, 1920, in the fifth inning of the fifth game of the World Series, against the Brooklyn Robins.