Valencia: Top-seeded David Ferrer of Spain beat Russia's Nikolay Davydenko 6-3, 6-4 on Friday to advance to the semi-finals of the Valencia Open, while Gael Monfils' bid for a berth at this month's ATP World Tour finals suffered a setback when the third seed was upset by unseeded Marcel Granollers in the quarter-finals.
The defending champion used a combination of speed and deep ground strokes to force Davydenko into costly errors throughout that match.
Ferrer won the first set as Davydenko struggled with his serve early, committing four double faults and repeatedly volleying long.
Ferrer broke the former world No. 3 in the fifth game of the second set before saving a late break point to ensure the victory on the indoor hard court.
"I began well and then later I had some trouble, but I was able to pull it out in the end," said Ferrer. "I feel good. I'm serving pretty well, but I still need to improve my game."
Ferrer will face Juan Monaco in one of two Spaniard vs Argentine semi-final matches after Monaco dispatched with Juan Carlos Ferrero 6-3, 6-3.
"Tomorrow will be a hard match," Monaco said. "All of us have reached the semi-finals in good form."
Earlier, Spaniard Granollers beat Monfils 7-6 (12), 3-6, 6-4 and will play sixth seed Juan Martin del Potro of Argentina in the other semi-final. Granollers, last year's runner-up to Ferrer, saved four set points in the first-set tie-breaker.
Monfils rallied to claim the second set, but Granollers took the match in two hours and 26 minutes when the Frenchman struggled with his serve late and sent his final forehand wide.
"These two years have been great for me here," said Granollers, who won his second ATP title in July. "Monfils is a tough player. He serves well and moves incredibly well. I had to play hard to beat him."
Monfils' early exit means he will have to win the Paris Masters, where he has twice finished runner-up, to have a shot at qualifying for the ATP World Tour Finals.
Del Potro increased his chances of making the eight-man, season-ending event in London by beating American Sam Querrey 6-2, 7-5. The five players ahead of Del Potro dueling for the final three places have either lost or withdrawn from their matches this week.
Del Potro dominated the first set and broke Querrey late in the second before winning the last game with his seventh ace of the match.
"I was a little nervous in the second set, but I ended up hitting some great forehands," said Del Potro, who looks to be getting back to something near his best after more than eight months out last year with a wrist injury. "(Granollers) is going to be tough, he's coming in with a lot of confidence."