**Tom Rogic scored a 90th-minute winner to secure a historic treble for Celtic as they completed an unbeaten domestic season.**In torrential rain at Hampden it was Aberdeen who took the lead through Johnny Hayes inside the first ten minutes.A corner swung in by Niall McGinn was met by Hayes who lashed a volley past Gordon in the Celtic goal to give the Dons the perfect start in the cup final.Brendan Rodgers men where looking to be the first Scottish side to complete an entire unbeaten season and where level only two minutes later through Stuart Armstrong.The midfielder broke free of his marker and lashed a left foot shot past Joe Lewis to give the Premiership champions an instant reply in Mount Florida.Despite the equaliser it was Aberdeen who continued to be the better of the two sides in the first half with chances from Ryan Jack and Kenny McLean saved well by Craig Gordon.Celtic also suffered an injury blow in the first half with Young Player of the Year Kieran Tierney having to be substituted due to injury.The youngster was caught by the elbow of Red's striker Jayden Stockley, with many suggesting referee Bobby Madden should have shown the red card.Celtic almost ended the half with a goal after Leigh Griffiths found Scott Sinclair in the box but the winger blazed his shot over from five yards out.Into the second half and Aberdeen continued their impressive start, and should have taken a 2-1 lead when Johnny Hayes found McLean free in the box but the Scotland midfielder couldn't control the ball and it remained goalless.As the game went on Celtic became the more dominant, creating chance after chance as Aberdeen began to lose control of the game.Chances from Sinclair, Roberts, Griffiths and Lustig all should have put the Hoops in front in the cup final, but for the heroics of Joe Lewis in goal.It took until the 90th minute for Celtic to break down the Dons defence, when midfielder Tom Rogic slipped in behind and blasted the ball past Lewis to seal victory for Celtic.The Scottish Cup trophy means Celtic have secured their first treble since 2001 and become the first team in Scottish football to go an entire domestic season unbeaten.