Crusaders remain six points ahead of Linfield in the Premiership title race thanks to a home victory over bottom-placed Institute.
Jordan Owens scored a close-range opener for the Crues on the half hour but the Seaview fans were stunned when Robbie Hume headed a superb equaliser.
Crusaders regained the lead through a Diarmiud O'Carroll penalty after Peter Bradley had fouled Declan Caddell.
Striker Owens headed in his 27th goal of the season to wrap up the home win.
For Crusaders, it was a 20th league victory of a season which looks like it could well end with the Gibson Cup returning to the Shore Road for the fist tie since 1997.
The league leaders could not afford any slip-ups against a side without a win in the Premiership since mid-October.
But they found it tough getting on top of Paul Kee's side who were four points adrift at the foot of the table.
Owens and Timmy Adamson had shots blocked before the Crues made the breakthrough in the 30th minute.
Billy Joe Burns headed the ball into the goal area and Owens stayed onside to beat keeper Marty Gallagher.
Seven minutes later Institute equalised when a long ball forward was superbly met by Hume who placed a brilliant header beyond home keeper Sean O'Neill.
Crusaders went 2-1 up in the 52nd minute through O'Carroll's penalty after former Queen's Park player Peter Bradley's challenge on Caddell.
Owens headed in from an acute angle four minute later to give the Crues a bit of breathing space.
Crusaders manager Stephen Baxter: "We were a bit disappointed to go in 1-1 at half-time. The players looked a bit anxious and I told them to try to relax.
"We got the penalty early in the second half and that calmed us down. We were on the front foot after that.
"The title race will look after itself. If we are six points ahead going into the split, it will be in our favour."