Ethan Devine grabbed another last-gasp winner as Linfield came from behind to beat Warrenpoint Town at Milltown.
Trailing to Steven Ball's 15th-minute header, the champions hit back with injury time goals in both halves.
Jordan Stewart rifled in the equaliser in the 46th minute, and Devine headed home the winner in the 92nd minute to seal three massive points for David Healy's side.
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It was another huge moment in the title race and sends Linfield four points clear at the top of the table.
"We knew it would be difficult coming here. Warrenpoint are fighting for their lives," goalscorer Stewart told Sky Sports.
"We didn't get off to the best starts and I am always disappointed not to play, but I came on and made an impact which is the most important thing.
"And Ethan scored the winner so it is a big, big day for us."
Warrenpoint went into the game on the back of a six-game losing streak but on another day could have emerged with a shock win.
Their opening goal arrived in the 15th minute.
A lofted ball was played into the box and Ball reacted first to head into the corner of the net, the ball rebounding off the inside of the post.
It was almost 2-0 in the 29th minute when Linfield keeper Chris Johns spilled Jonathan Leddy's low free-kick but recovered to deflect the follow up attempt over the bar.
The Blues levelled in first-half injury time.
Chris Shields delivered a free-kick to the back post, Jimmy Callacher headed it back across goal and substitute Stewart ghosted in to guide his shot into the bottom corner of the net.
Warrenpoint's goal led a charmed life in the 55th minute, but Devine had a shot blocked on the line before the young striker blazed the rebound over the bar.
The visitors were denied by another superb save in the 62nd minute when Conor Mitchell denied Jamie Mulgrew from point-blank range.
Warrenpoint could have reclaimed the lead in the 82nd minute when Alan O'Sullivan pounced on Ben Hall's poor backwards header, but after lobbing Johns the ball bounced on the hard surface and carried over the crossbar.
The champions finished the game in trademark fashion, with Devine the hero once again.
It came from Jack Hastie's inswinging corner, and Devine raced in to head home at the near post.
It was reminiscent of Devine's injury time winner against Crusaders two weeks ago, and it could yet prove another defining moment in this season's title race.
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