MADRID (AP) -- Rafael Nadal and Marc Lopez sealed victory for Spain in its Davis Cup World Group playoff against Ukraine, beating Sergiy Stakhovsky and Denys Molchanov in the doubles for an insurmountable 3-0 lead on Saturday.
Nadal and Lopez won 6-2, 6-7 (6), 6-3, 6-4 on the outdoor red clay at Caja Magica.
After Nadal and Fernando Verdasco won their singles rubbers on Friday, captain Alex Corretja paired the world No. 2 with Lopez to try and prevent the tie from going to reverse singles on Sunday.
Nadal, who won his 13th Grand Slam at the U.S. Open on Monday, still looked fresh despite the travel and playing two straight days.
Nadal and Lopez broke the Ukrainian duo's first two service games to set the tone as they extended Spain's unbeaten run on clay to 27 consecutive ties.
"We played at a good level,'' Nadal said. "In my case, I had a moment I felt tired but later we were able to recover. We achieved our goal and that's the important thing.''
This was the first time Nadal had played for Spain since December 2011, when he won the decisive point of the final against Argentina to earn Spain its fifth title.
Nadal's absence was due in part to a knee injury that sidelined him for seven months last season.
"Rafa's commitment to the team was critical and we have to be grateful for that,'' Corretja said.
In Belgrade, Canada set up a remarkable chance to reach its first Davis Cup final by winning the doubles against Serbia and taking a 2-1 lead.
Daniel Nestor and Vasek Pospisil beat Nenad Zimonjic and Ilija Bozoljac 6-7 (6), 6-4, 3-6, 7-6 (5), 10-8 in an exhausting match that lasted for four and a half hours on the indoor red clay.
"This is a heavy blow, but we still have the singles,'' Serbia coach Bogdan Obradovic said.
The result left the tie likely to be decided Sunday when top-ranked Novak Djokovic faces Milos Raonic, who took more than four hours to win his singles on Friday and then Janko Tipsarevic and Pospisil could meet in the decider.
Obradovic said "Pospisil will likely be tired after such dramatic two days.''
The doubles was exciting from the get go, with the Serbians favored. Zimonjic, with 27 doubles wins since 1995, has partnered with Bozoljac for seven years. Nestor, with 30 doubles wins in 21 years, and Pospisil had been a team for only two years.
The winner will face the Czech Republic, which defeated Argentina in the other semifinal.
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