ESSENDON midfielder Ricky Dyson will be sidelined for the next three matches after undergoing surgery to have his appendix removed when he was meant to be playing an AFL game.

Dyson, 22, was pulled out of the Bombers side to play Richmond last Saturday night after he experienced stomach pain that day, and he underwent an operation for acute appendicitis while the Dons were being beaten by the Tigers.

Essendon team manager David Calthorpe said Dyson was watching the match when he felt badly ill.

"Early in the first quarter it became clear he was in a bit of discomfort and one of our staff took him to hospital and he was operated on at 10pm that night for acute appendicitis," he said on Essendon's website.

"It's actually our second case of appendicitis in the past few weeks with Dean Dick also being operated on recently.

"In Ricky's case it was a far more aggressive form and he will miss three weeks compared to Dean, who had to miss two weeks."

Hawthorn's Luke Hodge also recently had his appendix removed, but that will have no impact on his return, as he is currently sidelined by a hamstring injury.

North Melbourne will be without star midfielder Daniel Wells for up to two games after he strained the medial ligament in his knee during Sunday night's win over the Western Bulldogs.

The Kangaroos are hopeful the injury will sideline him only for the game against the Brisbane Lions, but he could also miss the round 11 clash against Geelong.

North will also be without Jess Sinclair for up to six weeks, after he injured an ankle playing in the VFL last Saturday.

Gun West Coast on-baller Daniel Kerr is struggling to overcome a lower leg injury and remains in doubt for Saturday's clash with Collingwood at the MCG.

Kerr, who sustained the injury in the opening minutes of the AFL's Hall of Fame game earlier this month, was restricted to light duties at training on Monday.

West Coast assistant coach Peter Sumich said the club's main training session on Wednesday would determine whether Kerr and defender Beau Waters (groin) would line up against the Pies.

"We'll wait until Wednesday and hopefully they'll have a very good session and put their hand up," Sumich said.

Port Adelaide on Monday received good news about forward Brett Ebert, whose ankle injury is not as bad as first feared.

He is still a chance to play Fremantle on Sunday.

Also on Monday night, the Hawks were awaiting the results of scans on Stuart Dew's hamstring, amid speculation he might miss Saturday's big match against the Western Bulldogs in Launceston.

Dew suffered a hamstring injury earlier this season and was forced off the field on Sunday during the win over Melbourne.