The Thunder are now two wins out of a finals place as they chase an upset against the second placed Bulls at Greenfield Park.

Purtell is set to come off the bench in his first game in a month after a 40-8 loss to third placed Young last week.

The Thunder have switched things around and Robbie Byatt will move into halfback.

Purtell hopes it can help can some direction for the side.

He thought it was particularly telling in their tight loss to Kangaroos a fortnight ago.

"I think with a lack of experience we missed our opportunity to win that game in the 50 minutes we were on top," Purtell said.

However their most consistent performer this season, Jon Huggett, has shaken off the problem which saw him fail to finish last week and will start in the second row.

Southcity are unchanged.

READ MORE