CHRIS Fagan is without his best player, but the Brisbane Lions coach is still confident his team can upset a desperate Essendon at Etihad Stadium on Sunday.

Lions captain Dayne Beams suffered a strain to his AC joint that will sideline him for up to a month, but Fagan saw enough against GWS last week to suggest his young midfielders can fill the void.

Rhys Mathieson had a career-high 32 disposals, Hugh McCluggage earned a Rising Star nomination for his 19 touches, while debutant Alex Witherden (20) and Jarrod Berry (18 and one goal) also impressed.

Fagan said he was wary of the Bombers – particularly on the fast Etihad surface – but believed his team could spring a surprise.

"We had a close tussle with those guys back in round two," Fagan said.

"While we respect Essendon are a really good team on their day, we also give ourselves a strong chance."

He said playing without Beams for all but one minute last week was a good rehearsal.

"It gives us confidence," Fagan said.

"What we have to do is provide support around Dayne Beams and Dayne Zorko and Tom Rockliff with other midfielders, so it was really pleasing to see those emerging guys step up.

"The critical battle in footy is that ability to win contested ball, so the stoppages will prove critical."

Fagan said he respected the Bombers' forward line, which includes returning Cale Hooker and a small brigade led by Orazio Fantasia – who kicked five goals when the teams last met – but backed his young defence to quieten them.