In 2011, Grilli's career took off as a relief pitcher with the Pittsburgh Pirates. That year, he carried a 2.48 earned run average (ERA) and 10.2 strikeouts per nine innings (K/9) rate in 32 innings pitched (IP), and further improved in 2012, when his strikeout rate climbed to 13.8. In 2013, Grilli made his first All-Star team and became Pittsburgh's closer at the age of 36. From 2011 to 2014, he compiled a 3.09 ERA with 11.9 K/9, 3.3 BB/9 and a 34.2 percent ground-ball rate in IP.