In the A grade match, the Flies took a 6-0 lead at half time, thanks to a try from Jimmy Kepon in the 26th minute.
The Panthers came close to equalising on several occasions early in the second half.
However, the Flies were determined not to let the Panthers cross their line, holding them back with solid defence.
The Panthers narrowed the margin down to four points after a penalty goal in the 50th minute of play.
The scores were level at 6-6 seven minutes before full time when quick hands allowed Mark James to crash over on the wing.
It was left to former SP Hunters half back, Roger Laka, who had a difficult kick right from the sideline.
Laka's attempt to take the lead fell just short, setting up a thrilling last five minutes.
It would take something special to win the match for both teams and Flies half back, Benton Leme, was the man for the job, kicking a field goal in the 77th minute from 20 metres out.
From here, the Flies held on to win the match and pick up K22,000 in prize money.
The Panthers settled for K10,000.
In the U-20 men's grand final, Souths defeated Brothers 4-2.