All of the Glencross goals came in the third period after the Flames had built a 3-1 lead through the opening two stanzas.
He scored 1:14 into the final period, added a goal less than 5 minutes later and then scored into an empty net with 20 seconds to play. Glencross ran his goal total for the season to 12.
Mikka Kiprusoff allowed three goals on 20 shots, but was backed up by a busy offense that brought Calgary its second straight win.
Nashville has lost six of eight. Pekka Rinne was removed from the Nashville goal for the second straight game after giving up scores on Calgary's first two shots.
Rinne was also removed during a 7-4 loss Thursday in Vancouver.