Although not sure of the extent yet, Brisbane coach Chris Fagan says the knee injury suffered by first-year star Will Ashcroft has dampened his mood following the Lions' win over Geelong on Saturday night.

Ashcroft hobbled from the Gabba midway through the fourth quarter of the 11-point win holding his right knee and did not return.

Speaking after the match, Fagan was flat, but tried to remain optimistic about the 19-year-old's chances when he gets scanned on Monday.

"We'll all hope for the best," Fagan said.

"You've got to live in hope that it's something a little bit less than an ACL. We'll just see.

"It's dampened my mood.

"I don't like to see that for any player at any club, any time."

Fagan said Ashcroft, who was still hobbling around following the match, was "a little uncertain" as well.

Ashcroft has been fantastic for Brisbane in his first season after being taken at No.2 in last year's national draft, playing all 18 games and being an integral part of its midfield.

The injury soured an otherwise strong performance by the Lions, who led by as much as 37 points before having to hold on in the final 10 minutes from the fast-finishing Cats.

Fagan said although it wasn't ideal giving up the big lead, in some ways it was "fortuitous" to be able to train their end-of-game play after crumbling against Melbourne in the dying stages last week.

"I think we handled that last five or six minutes pretty well," he said.

"Psychologically it would have been pretty hard because those boys were aware of what happened last week.

"We never dodged away from what happened in the last part of that game.

"We reviewed it hard during the week and you could see they did the things we talked about much much better.

"You'd prefer to not have the opposition come at you like that, but in another way it's fortuitous that we got the opportunity to practise it.

"It wasn't perfect, but it was better."

Geelong coach Chris Scott said he didn't have to look far to see where things went wrong.

The Cats were hammered 49-22 in the clearances and 140-105 in contested possessions, which gave the home team a mountain of territorial advantage in the first half.

Scott praised his team's defensive group, saying they could have been "obliterated" with that much ball coming in.

"Our sense ... was that we got a lot wrong, didn't play particularly well, but hung in enough to give ourselves a chance to steal it," Scott said.

"It's such a nice feeling being the coach, knowing they won't give up. They were going to hang in and if there was a little opening they'd be there to jump through it." 

Although their top-four chances are now slipping away, Scott said he was still confident Geelong's best football was as good as any in the competition.