Nastu was a September call-up in 1978, appearing in three games for the Giants, with one of them a start, going 0-1 with a 5.63 earned run average over eight innings.
The following season he’d get decent playing time, appearing in 25 games and throwing exactly 100 innings while going 3-4 with a decent 4.32 ERA.
Sadly for him in 1980, after only six appearances, all out of the bullpen, he was was done in the Majors, as he posted a 6.00 ERA over six innings and was sent down to the Minors, where he’d go on to pitch the next two seasons for both the Chicago Cubs and Baltimore Orioles organizations before retiring for good after the 1982 season.
All told, he finished his MLB tenure with a record of 3-5, with an ERA at 4.50 over 34 appearances and 114 innings pitched.