Of course he knew Brian could defend himself against the attack made by Chris, though he knew it had been a good try, and quite a good tactic, though he is an expert Auror, so , he wouldn't be that easily defeated, and could be seen immediatly firing back a spell at Chris. A jet of water came his way, though he knew he could easily avoid it, as most wizards, since it wasn't a strong jet, so he couldn't be knocked off his feet. He flickered his wand, and turned the water away, landing on the floor, and making a slight pool around Chris. He got his feet a little wet , though it wasn't a problem. It seemed quite traditional duelling, these types of spells that is.
"Thanks."
He laughed a little as well.
"I do some gym once in a while, whenever I have time. Though I prefer jogging. Makes me be faster, and sometimes I play some reaction games so I can always keep my focus when I'm challenged. I consider to have quite good reflexes actually, though nothing compared to some of the best, but still."
Chris, was quite aware the duel hadn't ended, or atleast it didn't seem like it, and until he received the word, he would keep fighting. He flickered his wand, summoning one of the big crates on Knockturn alley, with a simple non-verbal Accio spell. He then threw it at Brian, following it with another spell.
"Petrificus Totalus!"