The Peabody native was a solid contributor for the Navigators in 2011, registering a 3.18 ERA with nine strikeouts in nine outings out of the bullpen.
As a freshman for St. Joseph’s, Gruntkosky went 4-3 with three saves and a 3.35 ERA, making 15 appearances with three starts. The right-hander fanned 35 batters with 41 hits and 11 walks in 37.2 innings pitched.
In 2012 Gruntkosky continued his roll pitching 43.2 innings for the St. Joe’s Monks while striking out 41 and posting a 3.09 era. Gruntkosky also appeared in 8 games, starting 6 of them with a 3-1 record to finish the year and ultimately winning the GNAC Championship.