Federer tops Istomin at Indian Wells
Federer, who won his fourth title here last year, lost just four points on serve, all in the first set.
Two of those were by double faults, and he never faced a break point and won 96 percent of his first serves.
"It felt good from the start and I was able to maintain that level of play," Federer said. "I never thought he got into the match at all. That gives you obviously even more confidence."
"I did what I could," Hewitt said. "I think I handled his serve pretty well and I made him hit a lot of balls.
"I felt like I had more chances throughout the match. The first set could have gone either way and then I dug deep early in the second set to get up a break. That was a big momentum change."
That set the stage for Rafael Nadal's first hard court match since March 29, 2012, because of a left knee injury that sidelined him for the final seven months of last season. Nadal faced American Ryan Harrison.
The second of the two service breaks by Hewitt, in game seven of the third set, gave the 2002-2003 champion a 4-3 lead. He added to it by holding serve for 5-3. Then, after Isner held for 5-4, Hewitt served out the match.
It didn't come easily, however. He got to 40-15 with a forehand pass, then lost three match points and fought off a break point before securing the win with a forehand down the line.
In other matches, Benoit Paire of France beat No. 20 Philipp Kohlschreiber, Jarkko Nieminen of Finland topped No. 28 Fernando Verdasco and Leonardo Mayer of Argentina eliminated No. 30 Mikhail Youzhny of Russia.
Copyright 2013 by The Associated Press
This story is from ESPN.com's automated news wire. Wire index
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