At 5:09 of the third period in the Penguins/Red Wings game, Detroit requested a Coach's Challenge to review whether Evgeni Malkin interfered with goaltender Jared Coreau before the puck entered the net.
After reviewing all available replays and consulting with NHL Hockey Operations staff, the Referee determined that Malkin's actions caused Detroit's Justin Abdelkader to contact Coreau before the puck crossed the goal line, preventing him from doing his job in the crease. The decision was made in accordance with Rule 78.7 which states in part: "The standard for overturning the call in the event of a 'GOAL' call on the ice is that the Referee ... determines that the goal should have been disallowed due to 'Interference on the Goalkeeper,' as described in Rules 69.1, 69.3 and 69.4."
Therefore the original call is overturned - no goal Pittsburgh Penguins.
Since the Coach's Challenge resulted in the original call being overturned, the Detroit Red Wings retain their time-out.