I guess he hasn't been playing as well as they would like him to.
He'll probably get to play now that Mark Rycroft has been injured.
Here is what it said in the T&G.

"Brown a healthy scratch.
Marc Brown was a healthy scratch for the third time in four
games. While Brown is off to a slow start, he hasn't found a place
in the doghouse, or anything like that.
'He's playing OK,' Granato said, 'but he can play better. When
everybody is healthy, it can be a complicated situation when a guy
gets bumped from the lineup. With the way our wingers have been
playing, I haven't felt the need to make a change.'
'I'm not happy about it,' Brown said, 'but maybe this is a
wakeup call. It's not that I've played badly, I don't think, but I
can play better in my role. If I get back to doing the little things
better, the goals will come, I know, but I have been gripping the
stick a little tight.'"