Brown hyper-extended a knee in a third quarter marking contest against the Roos, creating plenty of tension in the home crowd of just more than 22,000.
But the Coleman Medallist returned later in the term and kicked his sixth goal in the final quarter to help seal a 31-point win.
"When anyone goes down with a knee issue and hobbles off you really don’t know what it’s all about,” Matthews said.
"So we’re pretty happy it’s not too serious. He did something similar against Sydney in the last (pre-season) practice game – he was almost stretchered off and was then back running within five or 10 minutes.
"It’s now a question of how he pulls up for next week. Sometimes you are able to finish the match and then it’s still a bit inflamed after.”
The Lions were something of a “walking wounded” by the end of Saturday night’s clash, with Brown not at 100 per cent, Joel Patfull limping in the wake of a third-quarter lower leg injury and Ash McGrath, Jason Roe and Josh Drummond all on the bench with hamstring tightness.
Matthews is optimistic of all being fit for selection for the Fremantle clash, but is confident the Lions have plenty of depth from which to draft potential replacements.
With Patfull and Drummond hampered, young tall Mitch Clark spent some time in defence and looked far from out of place.
”When it happens, the load gets less spread – we had three guys who tightened up in the hamstrings,” Matthews said.
”What that means for the future I don’t know yet. They didn’t seem to do anything really bad but they all suffered. We were down to 19 players in the end.
”Mitch is more than capable of playing tall defence, ruck or key forward. He gives us pretty good flexibility.”
After being critical of his side’s last quarter efforts in the round nine win over St Kilda, Matthews was far happier with the Lions’ ability to run out Saturday’s game.
”The game was probably a bit more live at three-quarter-time than it has been in the past few weeks,” Matthews said.
”We did a good job tonight. I think we got outscored in the second half but we actually ran the game out really strongly given we were a little bit down on personnel.”
