Linfield took a huge step towards retaining the Premiership crown with Robert Garrett getting the winner against second-placed Crusaders.
Garrett scored in the 86th minute with a thumping right-foot finish after substitute Michael Carvill had pulled the ball back from the bye-line.
Linfield went closest to a breakthrough in the first half when Mark McAllister's header hit a post.
Tempers flared after the final whistle with players squaring up to each other.
Several had to be separated by team-mates and attendants.
That was in contrast to a tame second half with Crusaders only showing urgency after going behind.
The result puts Linfield three points clear of Crusaders and the champions also have a game in hand and a much superior goal difference.
"It was a competitive game and we went out to try and win the match," said Linfield manager David Jeffrey.
"But there is still a lot of football to be played.
"People said it was all over when we were 10 points clear. Tonight has not decided where the title will be going.
"We still have to play Glentoran twice, Cliftonville, Portadown and Distillery."