NRL referees boss Tony Archer has admitted that Manly fullback Brett Stewart came from an offside position in his match-deciding try that ended Canberra's season on Sunday.
The Raiders were leading 24-20 when Stewart finished off a Daly Cherry-Evans line break in the 77th minute to steal a thrilling win and keep their finals hopes alive.
Replays have since shown that the Sea Eagles star came from an offside position, having run through the defensive line on the prior tackle.
The rules state that for an attacking player to be onside when he is in front of the play the ball, he must retire or retreat behind his player involved in the play the ball.
And while Stewart was walking back into the attacking line, Archer said he hadn't come back far enough.
"After viewing footage of the play, including eagle cam, Brett Stewart retreated to the ruck area, between the marker and the point where Jorge Taufua played the ball," Archer told AAP.
"It was a judgment call made live by the officials and it was a close decision, particularly with Jorge Taufua walking forward in front of Stewart.
"However technically Stewart does not retreat the required distance."
The admission will be of little consolation to Canberra coach Ricky Stuart and his side, who have now fallen four points adrift of 8th-placed St George Illawarra with just three games to go in the season.
But for the Sea Eagles, the win lifts them to 24 points, equal with the Dragons, but they sit one spot behind due to an inferior points differential.
Manly host struggling Parramatta at Brookvale Oval this Sunday.