Brown said: "I don't know how he stopped it.
"He kept us in the game. I think he got his big toe in the way of it!
"He said at half-time that he felt he should have done better with their goal, so to come out and make some good saves in the second half was fabulous."
Brown was delighted with spirit United showed to fight back from a goal down.
He added: "We came out in the second half and got straight back at them.
"I think we deserved the goal that Rooney scored although we were a bit lucky with the own goal. But you take anything and everything you can get. It was a great ball in from Giggsy. I'm not sure there was any real danger - I think Diaby just misjudged it and headed it in.
"Beating Arsenal was a great result - we need to keep going now."