Nikolay Davydenko was just the man to offer a tough test for a new member of the Top Ten Club on a hot, humid day at Key Biscayne.
John Isner, to his credit, passed in his opening match in the Sony Ericsson Open -- but it was never easy.
Isner came through 2-6, 6-3, 6-4, getting his act together after what he called an ugly first set and serving out with a flourish -- four first serves clocked at 137, 135, 136 and 129 mph.
How big is that? Huge in terms of winning a tennis match against a talented opponent, and it offers clear proof of just how high Isner's confidence is right now after a start to the year that has seen him beat Roger Federer on clay in Davis Cup and Novak Djokovic on his way to reaching the final at Indian Wells last week.
"It comes from winning matches," Isner replied when asked about his confidence.
"When I have the chance to serve out the match, the match is completely on my racquet, and I'm confident on my serve. So, for instance today, I had 0-30 in the p...