What do you think that Ivo Karlovic has (apart from an inch in height and 15lbs less in weight) that John Isner hasn't? I only ask as I saw Andy dismantle Isner at the AO in 3 sets.
I've also seen Karlovic at the AO, and if I recall correctly, he lost in straight sets to Nadal, the year he lost to Ferrer, so 2010? I can't check on the ATP tour website because it's playing up
Yes, Karlovic has won 3 titles on grass but he's also gone out in the 1st round in Wimbledon in the same year those titles were won.
He comes across as a nice player but obviously hasn't the range of shots that Andy has.
I hope that Andy's serving is as good, or better, than on Tuesday, and that he's able to latch on to those returns pretty quickly.