Galasso pitched in 55 games during parts of three seasons spent in the big leagues. He appeared in 11 games for the Seattle Mariners in 1977, then returned for 31 games with the Milwaukee Brewers in 1979 before concluding his big-league run with 13 more games for the Mariners in 1981. In 118 innings pitcher Galasso went 4-8 with four saves and a 5.87 ERA. Most of Galasso’s time came for the Brewers in 1979. He pitched in 31 games that season, compiling a 3-1 record and a 4.38 ERA.
The longest game in Fenway Park history took place on September 3, 1981. The game was eventually suspended in the top of the 20th inning and concluded the following day. Galasso threw three innings and gave up three hits but no runs to collect the win.