Querrey was the only player to take a set of Andy at the US open juniors in 2004. To be honest he was the only player to come close and he took Andy to a tiebreak in the second set. At the time I thought it was because Andy was just over confident having cruised through 3 matches, however, having followed this match I think there must be something in Querrey's game the really bothers Andy when he isn't on top of his game. Andy will need to concentrate hard to end this match with a minimum of effort.