The Scotland star, who could be about to play his last game for the Warriors ahead of a summer move to Saracens, starts in the No6 shirt in a contest that he views as the biggest in his club career.
And if the prospect of reaching the inaugural Magners League Final isn't enough on its own, Brown has the added incentive of finishing his Glasgow career on an almighty high with two more wins.
It would give the 27-year-old the perfect send off and that's exactly what he's aiming for.
"This is absolutely massive. In terms of my club career it's definitely the best achievement," said Brown, who has featured in 14 of Glasgow's 18 Magners League games so far this term.
"It's the biggest game in the club's history and one we are very much looking forward to. The quality of play and the intensity of the game will be international standard.
"This is the inaugural year for the play-offs in the Magners League, so it's very exciting to be involved in that. But I'm not content getting into the semi-final - I want to take the next step.
"It's massive for me to leave on a high note. What a finish it would be to win the Magners League.
"As a side, we have grown all year and if we could get to the final and go one step further then that would be a fantastic way to finish my career here."
Achieving that big send-off won't be easy, though, and Brown certainly isn't underestimating the size of the challenge that lies ahead in Swansea tonight.
The Ospreys named 15 full internationals and eight British & Irish Lions in their starting XV yesterday, with two former All Blacks and the Wales skipper lining up opposite Brown and co in the back row.
Add in the fact that the Ospreys are on home soil and haven't lost at the Liberty since early November and the task becomes even more daunting.
"It's a massive, massive challenge," added Brown.
"Their side is like a World XV. They have got so many Lions and so many All Blacks. They are jam-packed full of quality players, so it's a very big challenge for us.
"But we are packed full of internationals as well, so there's no doubt we can go in there and put in a good showing and get the win.
"As players, you want to test yourself against the best and there is no doubting this Ospreys back row is one of the best in the world.
"We've got to go down there and take the game to them. If we just try and hold on and sneak it, we've got no chance at all.
"If we play as we can, then we can get the result we want."
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