Hard to know which baseball metaphor to use here. To say this Sideway Theater production strikes out doesn't work since striking out is statistically normal. Even suggesting that it hits into a triple play seems inadequate, while calling it Cubs-like falsely implies that it shares the Cubs' loser charm. Maybe if a Cub somehow struck out into a triple play . . . ? Mr. Baseball wants to be about the tragic final moments of a former slugger's career, but neither playwright Matt Doherty nor director Michael Stock tells that story clearly, credibly, or competently. To take just one jaw-dropping example: in what's meant to be a horrific moment, a character is bludgeoned with a bat that's apparently made of foam and therefore bends with each whack. --Tony Adler a Through 5/27: Thu-Fri 7:30 PM, Sat 2 and 7:30 PM, Sun 5 PM, Aguijon Theater, 2707 N. Laramie, email@example.com, $14.99-$19.99.