Funny thing for me is I choke when I play doubles but hardly when I play singles. I had a hard time getting into a rhythm and found myself worrying about setting up my doubles partner for the next point. I ended up thinking too much. Also, I noticed my doubles partner is having problems as well, he's a great singles player (he really bad on doubles - does not know about court spacing, he likes to crowd the net even when I am returning a serve). We got beaten badly by our opponent ( a 3.0 / 4.0) player while me (4.0) and my partner a (4.5 or 5). I really enjoy playing doubles but I found that it really requires more team work and knowing your court position to play good a this game. Well, it a definitely a new challenge for me.