Midfielder Hiram Boateng provided an assist in Mansfield Town's 2-1 defeat at home to Sky Bet League Two champions Leyton Orient.
Orient had the better start, with Kieran Sadlier shooting from 30 yards inside the first minute, only to be stopped by Alfie Kilgour's strong block.
Mansfield used their momentum to score the game-winning goal in the 10th minute. Hiram Boateng's move into the area got Mansfield in behind the champions' backline before the midfielder picked up Keillor-Dunn five yards out. The pass was intercepted by the Stags' number 40, who comfortably turned the ball into the bottom corner to give Mansfield an early lead.
In the 17th minute, the visitors rallied and drew level. Jamie McCart's effort from outside the area deflected against the inside of the post, allowing striker Charlie Kelman to head home from close range.
In the 31st minute, Ruel Sotiriou strongly converted Sadlier's cutback ball with a first-time strike into the bottom corner for Orient to make it 2-1.
Ollie Clark replaced Hiram Boateng in the 80th minute.