Blake overcame his fifth-set woes, fighting off two match points to beat Paul-Henri Mathieu 7-6 (5), 6-7 (3), 6-3, 3-6, 7-5 on Friday to give the United States a 2-0 lead in the best-of-five series.
Andy Roddick ripped 30 aces on the fast hard-court in a 6-4, 7-6 (3), 7-6 (5) win over Michael Llodra in the opener.
The American's top-ranked doubles team of Bob and Mike Bryan can put the United States into the semifinals with a win today against France's likely pairing of Llodra and Arnaud Clement. The reverse singles are Sunday.
Blake, who lost the first nine five-set matches in his career, has now won three of four. He appeared finished when Mathieu had two match points serving at 5-4 in the fifth set. But Blake battled back, then broke Mathieu for the fourth time to close out the nearly four-hour match.
Blake jumped in the air and was quickly embraced by his teammates, including Roddick, who took a much easier path against Llodra for his win.
Llodra had 26 aces of his own in a powerful, if unexpected, matchup after Australian Open finalist Jo-Wilfried Tsonga withdrew earlier this week because of a right knee injury.
With Richard Gasquet slowed by a blister on his right hand, French captain Guy Forget went with Llodra, who also is expected to play in today's doubles. The strong left-hander constantly attacked the net and had his serve broken only once, but he couldn't overcome Roddick's blistering serve.
"I thought he played well and I had to play really good stuff today to get through," Roddick said.
Roddick fended off his first three break points at 5-5 in the third set, closing out the game with consecutive aces. Fittingly, he converted his second match point in the third-set tiebreaker with a service winner.
- In Bremen, Germany, Rafael Nadal easily beat Nicolas Kiefer 7-6 (5), 6-0, 6-3 in the Davis Cup quarterfinals, and David Ferrer also won to give Spain a 2-0 lead.
If Spain wins, it will face either the defending champion United States or France in the semifinals.
- In Moscow, Marat Safin, who has struggled with a 1-5 record on the ATP Tour this season, overcame a two-set deficit to help Russia earn a 1-1 split with the Czech Republic.
Safin, who was added to Russia's team after the official team nominations were released last week, rallied to beat Tomas Berdych 6-7 (5), 4-6, 6-3, 6-2, 6-4. But Radek Stepanek recovered one point for the Czechs by defeating Igor Andreev 6-3, 6-2, 6-4.
BAUSCH & LOMB: In Amelia Island, Fla., Lindsay Davenport and Maria Sharapova set up a semifinal showdown today in the Bausch & Lomb Championships, winning quarterfinal matches.
"It"s always going to be a challenge against Lindsay," said Sharapova, who is 5-1 lifetime against Davenport. "She's had great success here, and shes always been a tough opponent on any surface."
In the quarterfinals, the top-seeded Sharapova beat No. 10 Alona Bondarenko 6-7 (9), 6-3, 6-2.
Davenport, the No. 16 seed and a three-time Bausch & Lomb champion, advanced with a 6-4, 7-6 (3) victory over No. 8 Agnes Szavay.