Celtic and Aberdeen went head to head for the Scottish Cup in Hampden Park.
The Dons had the better of the opening stages, pressing Brendan Rodgers side, and winning a pair of corners. From the second of these, Johnny Hayes steamed in at the back post to sidefoot in from Niall McGinn's corner. The midfielder, named in Martin O'Neill's Irish squad for the upcoming game, had escaped from Leigh Griffiths' shambolic attempt at marking.
The lead lasted less than two minutes. The Hoops put together a nice passing move, with the ball ending up at the feet of Stuart Armstrong. He fired brilliantly into the bottom corner for an immediate equaliser.
You can see both goals below.
Aberdeen Celtic goals
Armstrong's 17th goal of the season has the game set up to be an absolute corker.
Brendan Rodgers' side are looking to complete the domestic season unbeaten.