Caversham beat University, while Roslyn-Wakari downed Grants Braes.
Dunedin Technical lurks in third place with a game in hand, to be played next week against Northern, and this match could decide whether the Gardens club achieves a top-six finish or not.
The top three sides, along with Mosgiel and Queenstown, have already qualified for the top six, to be joined by either Green Island or Northern.
The South Island grand final is not until September 27.
Tim Cook led Caversham's dominating performance over University at the Caledonian Ground with a classy hat trick. Opening the scoring after 30min with a diving header, Cook admitted he could have doubled his tally.
"After some initial resistance, we should have scored more. There was so much space available in the Varsity goal area," said the former Golden Boot winner.
University narrowly heads Grants Braes on goal difference at the bottom of the competition.
There were some good individual performances by James Vaughan, Liam McKinlay and Dan Peacock who went closest to scoring.
Coach Steve Fleming was initially concerned his side might not reproduce the excellent form that sank Dunedin Technical 5-2 last week.
"It's hard to generate that quality week in and week out," he said.
Fleming named defender Rhys Henderson as the pick of his side.
At Ocean Grove, Sean Brand and Jamie Taylor grabbed two goals each for Roslyn, with Paul Steele completing the scoring.
