BRISBANE could be without Jack Gunston for the rest of the season after the forward suffered a suspected medial collateral ligament injury in Saturday night's win over Adelaide.

The three-time premiership Hawk buckled under a tackle late in the first half of the six-point triumph, hobbling to the bench and not returning.

Speaking after the match, Brisbane coach Chris Fagan kept the door slightly ajar for a Gunston return later in the season, but the odds appear slim.

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"The early prognosis is an MCL and probably four to six weeks," Fagan said.

"It didn't look too good when it happened. I'm not sure whether Jack will get back this year or not."

Gunston has kicked 22 goals from 17 matches in his first season as a Lion, looking more potent since he returned from a three-week break for a mid-season training block.

Fagan was pragmatic about the potential loss of one of his tall forwards after also losing Will Ashcroft (knee) recently, saying every team was having injury battles.

"That's the war of attrition that an AFL season is," he said.

"It's unfortunate for him because I felt like he's been building a bit since he came back.

"They're just the breaks in footy. You've just got to take that stuff on the chin."

Gunston's injury was the sour note to a victory that secured a top-four spot for Brisbane for the fourth time in the past five years.

It wasn't easy though after conceding the first three goals of the game and then watching a 22-point fourth quarter advantage get whittled all the way down to six points.

Fagan said his team looked "tired" at the end of the match and conceded things could have gone differently.

"I knew at three-quarter time they (Adelaide) were going to keep coming at us, which they did, and in some ways they deserved to win today, I would say.

"In another way I'm proud of the fact our players are able to dig deep after a slow start, get themselves back into the game, play a good third quarter and then hold on.

"I thought the last minute and a half we did it pretty well."

Adelaide coach Matthew Nicks was left to rue yet another close loss for his team, the fourth defeat by a goal or less to a top four team.

"Very disappointed, we all are," Nicks said.

"We've got all the ingredients there. We're not getting it done. We've just got to get better.

"We want to be a great team, at the moment we're a good team, in fact we're a very good team, taking it up to the best all year.

"We want to be better than what we are at the moment."

The Crows generated more inside 50s and had more scoring shots, but missed a number of chances in the final 10 minutes when a wobbly Lions appeared there for the taking.

Nicks said it was the "key moments" that cost his team but had not given up on an unlikely spot in the top eight.

"We haven't been consistent enough," he said.

"We're still in the fight, so we're still a chance with two rounds to play in the season."