Top seed Andy Roddick fought off Australian Chris Guccione 6-3 6-7 7-6 at the San Jose Open on Wednesday, setting up a second round tie with Japanese teenager Kei Nishikori.
Nishikori beat Diego Hartfield of Argentina 7-5 6-3 while third seed Tommy Haas also scored a first round win over Robert Kendrick 6-3 4-6 6-2.
In second round matches, fourth seed Radek Stepanek of Czech Republic overcame American Bobby Reynolds 7-5 7-6. Robby Ginepri of the United States beat eighth seed Kristof Vliegen of Belgium 6-2 6-3.
"I thought I outplayed him from the start, but I'm just glad I have something to show for it," said American Blake, the world number six.
"It's a bit of a mental grind. It's the sort of match where you can play horribly and win, and play well and lose."
Roddick, who led the U.S. Davis Cup team to a first round victory over Austria in Vienna on clay 10 days ago, seemed to take a while to get used to the indoor hard court.
He broke Guccione to 3-1 in the first set and comfortably sat on the lead to win the set. But the Australian showed his fighting qualities to take the second set in a tiebreaker, coming back from 3-0 down to tun off seven points in a row.
"I played a sloppy double fault and then he put some shots together and all of a sudden we are in the third," Roddick said.
The final set went to another tiebreaker, which Roddick sealed 7-5 with an unreturnable second serve.
Nishikori, Roddick's opponent in the second round, is coming off his first ATP title win in Delray Beach last week and admitted to being mentally tired.
Roddick watched the Japanese 18-year-old beat Hartfield.
"I wanted to play Roddick, that's why I won today," Nishikori said.
"When I was at 4-3 and saw he was watching, I got so nervous. For two games I couldn't move."