THE CONTROVERSIAL free kick that set up West Coast's after-the-siren win over North Melbourne on Friday night has been ruled correct by the AFL.

Kangaroo Leigh Adams was penalised for tackling Eagle Adam Selwood high.

Selwood's resultant free kick sent the Eagles deep into attack, where Nic Naitanui took a sensational pack mark, then kicked the winning goal after the siren.

While Selwood appeared to lower himself to draw the high contact, umpires boss Jeff Gieschen said replays showed the contact did occur, so had to be penalised.

"The umpire was in a good position to see that, saw it, paid the free kick as he saw it and there is high contact there," Gieschen told AFL.com.au on Monday.

"The timing of it, the lateness of the game and all those sorts of things creates a lot of emotion about it.

"But if an umpire sees that high contact, he's obliged to pay that high contact, which he did."

But Gieschen did admit to one weekend umpiring blunder, with an official failing to make Geelong's Corey Enright go behind his mark, after taking a mark against Collingwood on Saturday night.

The umpire ordered Enright to go behind the mark but, when the player ignored that instruction, the umpire simply let him play on.

"That was a really interesting one ... that was an error by the umpire," Gieschen said.