The Scorpions go into the clash in a logjam of four teams tied in fifth place on eight points.

A loss against the Roos could result in Macquarie losing touch with the crucial five semi-final places.

Last week the Scorpions went down 28-14 to Kurri Kurri, who moved into outright fourth on 10 points.

Six points separate the bottom seven sides, from Kurri to last-placed Lakes United.

Club secretary Steve Woodbridge said dropped ball and penalties at crucial times stopped the Scorpions applying pressure to the Bulldogs last week.

"The commitment from the players is there, but the execution is lacking, making it a very frustrating day for the coaching staff and supporters,'' he said.

Macquarie's reserve grade missed the chance to snatch top spot on the ladder when they lost 17-16.

Kurri Kurri kicked a field goal in the dying minutes for victory.

The under 19s drew 28-28 after trailing the Bulldogs 24-6 at half-time and scored in the final minute to level the scores.