Linfield will clinch the Premiership title if they beat Portadown on Saturday after Cliftonville were beaten at Coleraine on Friday night.
Aaron Boyd hit Coleraine's winner on 21 minutes after Reds keeper Ryan Brown had saved a Curtis Allen effort.
Allen headed against the Reds woodwork in the first half with Stephen Garrett missing a Cliftonville chance.
Liam Boyce and Shane Jennings went close at either end before Coleraine survived a late Cliftonville onslaught.
Boyce's scissor-kick scraped the Bannsiders crossbar on 71 minutes while Reds keeper Brown dived bravely to deny Coleraine substitute Shane Jennings.
Cliftonville, sensing that their hopes of securing second place in the table were receiving a major blow, produced intense late pressure with Garrett inches away from notching an equaliser.
In the first half, Reds keeper Brown denied Ryan McIlmoyle with a superb pointblank save while Garrett dragged a chance wide at the other end.
The winning goal came after Brown superbly saved Allen's initial shot with David Scullion unselfishly squaring for Boyd to tap to the net.