I wasn't able to catch all of this rain-delayed, 13-inning mess, but kudos if you stuck around for all of it. The outline:
The Reds scored in both the first and second innings, but the Bucs came back to take the lead in the bottom of the second, as Neil Walker walked, Francisco Cervelli reached on Eugenio Suarez's error, Jordy Mercer hit a ground-rule double, and A.J. Burnett hit a two-run single. The Bucs tacked on a run in the sixth after Burnett grinded his way through the middle innings, allowing plenty of baserunners but keeping them from scoring.
Arquimedes Caminero relieved Burnett in the seventh and gave up a leadoff single to Joey Votto, who went to third on Josh Harrison's error. Then Caminero threw a 99-MPH fastball down the middle to Todd Frazier, who can hit those. It went for a two-run homer as the Reds tied the game at four. Caminero allowed a couple more baserunners before Antonio Bastardo (who's quietly been very good lately) finally cleaned up the mess.
After that, the Pirates failed to score on a series of unimpressive Reds relievers (and Aroldis Chapman, who pitched one inning). Tony Watson and Mark Melancon pitched the eighth and ninth, respectively, then gave way to Vance Worley, who got through three scoreless innings. Rob Scahill took over in the 13th and gave up a leadoff homer to Brandon Phillips, and the Pirates failed to score against Pedro Villarreal in the bottom of the inning.