Ten-man Celtic's unbeaten run at the top of the Scottish Premiership is in jeopardy as they trail Aberdeen 1-0 at half time.
Anthony Stokes almost fired the visiting side ahead with just two minutes on the clock, but the striker's low shot was well saved by Jamie Langfield.
Disaster struck for Celtic with 12 minutes played as Virgil van Dijk brought down Peter Pawlett who was bearing down on goal, with the defender receiving a straight red card.
Aberdeen eventually found a way through four minutes before the break, with Jonny Hayes beating Fraser Foster with a strike from 25 yards out.
The second soon followed courtesy of Adam Rooney, who stooped down low to convert a cross into the box and double his side's advantage on the brink of half time, leaving the Hoops with a mountain to climb.