The Ocean Kinetics Premier League will be decided in the final fixture after Spurs missed the chance to clinch the title on Monday night.
Scalloway beat Spurs 2-1, with goals from John Allan and Jack Fitzsimmons, while Ness hammered Whalsay 4-0.
That means Ness sit top of the table after their final fixture – with Spurs two points behind and with one game to play.
They take on third-placed Whalsay at the Harbison Park on Friday evening.
Ness have not won the league for over 50 years, but will end that wait this week if Spurs fail to beat Whalsay on Friday.
Spurs, meanwhile, are looking to retain their league trophy.