If you're against the traditional closer role, with the belief that your best reliever should be used in the toughest situations, then Felipe Rivero's current usage is nearly perfect. Rivero is easily the best reliever in the Pirates' bullpen, and one of the best relievers in baseball this year, but is currently the set-up man to Tony Watson. And that set-up role gives the Pirates some flexibility.
Take Tuesday's game, for example. Ivan Nova gave up two homers to start off the seventh inning, cutting the Pirates' lead to 4-3. After being lifted with an injury, he was replaced by Juan Nicasio, who put the tying runner on base.