BIRMINGHAM, Ala. — Melanie Oudin defeated Alla Kudryavtseva 6-3, 6-3 today, but Russia's Elena Dementieva evened up the Fed Cup semifinals matchup with a straight-set win over Bethanie Mattek-Sands.

Dementieva, ranked No. 6 in the world, won 6-4, 6-3 to set up a big Sunday rematch with Oudin in the best-of-five tie.

The 18-year-old Oudin, ranked a career-best 31st, rallied from two games down in each set to win the match at the Birmingham-Jefferson Convention Complex Arena. She fell behind 1-3 and 0-2 to the Russian, who was making her Fed Cup debut.

Oudin took control after the slow start, breaking Kudryavtseva's serve three straight times in the first set.

"I was missing a couple of shots that I normally make," Oudin said. "I knew I had to hang in there and make her hit a lot of balls, and then she started making some errors and I started playing better and being more aggressive. I was able to close out the first set very well."

Dementieva capitalized on 43 unforced errors by Mattek-Sands in a matchup of players with aggressive styles to win the second singles match. Mattek-Sands is ranked 129th.

"She wanted to make some spectacular shots, going for the winners," Dementieva said. "It was not easy for me to play because of the situation (down 0-1). There's always a little more pressure when you have to win your match. It was not an easy win for me."

Defending Fed Cup champion Italy took a 2-0 lead over the visiting Czech Republic in the other semifinal, where Flavia Pennetta and Francesca Schiavone each won in straight sets. The U.S., which would host the final round on Nov. 6-7 at a site to be determined, lost to Italy for the title last year.

The second match set up the potential for some final-day drama.

"We're happy," U.S. captain Mary Joe Fernandez said. "Both Bethanie and Melanie played their hearts out, they competed extremely well. That's all that I can expect from them."

Oudin was down 0-2 in the second set and facing game point after losing a point on a ball she thought was long, dropping her racket and covering her face in exasperation.

She then fought off two game points and won the next three games.

"I think I started well, considering how nervous I was," Kudryavtseva said. "I guess I just got more nervous as I went on. Melanie played well. She fought and was there every point.

"I did feel a lot of pressure. I don't think I've ever had so many people cheer so aggressively against me."

Oudin, who is from suburban Atlanta a couple of hours away, will face Dementieva in reverse singles on Sunday. She is 1-1 in career meetings against her.

"Elena's going to be the tough one on the team for us," Oudin said. "I knew I really needed to try to beat Alla today because Elena's going to be really tough. I was really happy to be up 1-0. This was the first time I've ever played the first match in Fed Cup, so I liked it better, I think."

Mattek-Sands will play Kudryavtseva or Ekaterina Makarova on Sunday, then team with top-ranked doubles player Liezel Huber. Dementieva and Makarova are scheduled to team up in doubles for Russia.

Russian captain Shamil Tarpischev said he would consider changing his No. 2 singles player.

"I'll be ready for both and I'm sure Melanie's ready for Elena again, too," Mattek-Sands said.

Kudryavtseva was impressed by the 5-foot-4 Oudin, and so was Dementieva.

"She's tough. She doesn't give anything," Kudryavtseva said. "You give her a little chance, and she's right on it. She has the guts, she has the courage to go for it no matter what the score is or what the situation is, and that's why she's so good."

Dementieva knows Oudin will have the fans behind her, including a sizable contingent of friends and family from home.

"It's a big advantage to play near your hometown and have the crowd support," the Russian star said. "For us on the Russian team, it's never easy to play in the United States but this is what we like about Fed Cup: The crowd is very involved in the game and very emotional."