The title will be settled in what is the final game of the regular season for both teams, after the Giants' title hopes were resurrected by Sheffield's defeat at Chester Jets last weekend.
Scantlebury said: "Playing in my 500th game means a lot, but not as much as winning the league. This would be the icing on the cake. It just seems amazing it has come down to this last game; that means so much."
Scantlebury began the season on 466 games, tied with the retired Ken Nottage, and made 11 appearances for Newcastle Eagles before transferring to Sheffield, where he has added a further 22.
Scantlebury won the league title with Thames Valley Tigers in 1994 alongside Tony Holley, who plays against him tonight for Manchester.
Midweek results have clarified the play-off positions. The Tigers' 96- 80 win over Leicester guarantees them third place, with London Towers now certain to finish fourth.
The Sharks, Giants, Tigers and Towers will have home advantage for the best-of-three play-off quarter-finals. Derby Storm, Birmingham Bullets, the Eagles and Greater London Leopards complete the last eight, with the pairings being decided by this weekend's results.