Cosgrove had a very nice showing over those 13 games, posting an earned run average of 1.80 over 10 innings while going 1-1, all out of the bullpen.
His first taste of the Big Leagues was a season earlier when he came up for seven games, going 0-1 with an ERA of 4.61 over 13.2 innings, with a start thrown in.
He would go on to play five years in the Majors, all with Houston, finishing up with a record of 12-11 with an ERA of 4.03 over 119 appearances and 274.2 innings pitched, striking out 122 batters while walking 145, collecting eight saves between 1972 and 1976.