(CNN) -- American Andy Roddick clinched the eighth and final place for the ATP World Tour Finals on Thursday, but world No. 3 Novak Djokovic suffered a setback in his preparations for the season-ending event.
Roddick qualified for the November 21-28 tournament in London after ending Jurgen Melzer's hopes by beating Ernests Gulbis at the Paris Masters -- and then seeing closest rival Fernando Verdasco lose.
Roddick, seeded eighth for the French event, won 6-3 7-6 (10-8) against his Latvian opponent, then his place for the finals was secured for an eighth straight year when Verdasco lost an epic third-round tussle with home player Gael Monfils.
The Spanish sixth seed went down 6-7 (4-7) 7-6 (7-2) 7-5 to the French No. 12, meaning that his compatriot David Ferrer and Tomas Berdych also secured places in London despite losing on Thursday.
Czech fifth seed Berdych qualified for the first time, but then promptly went down 4-6 7-6 (7-5) 6-0 to Russian No. 10 Nikolay Davydenko.
Spanish seventh seed Ferrer went through despite losing to Melzer, with the Austrian No. 11 prevailing 7-6 (8-6) 2-6 6-3 to set up a quarterfinal showdown with world No. 2 Roger Federer.
"Yes, I lost, but I'm really glad, because it's very nice to come back to London," Ferrer told the ATP Tour website. "I have played a lot of matches, but this year I play less tournaments than the last two, three years.
"It is very nice come back to the top 10. Now I want to relax two or three days, and I will prepare one week for London."
Roddick will play fourth seed Robin Soderling in the last eight in Paris following the Swede's 7-6 (7-3) 6-3 win over Swiss player Stanislas Wawrinka.
Defending champion Djokovic was surprisingly beaten by Michael Llodra, who the Serbian may face again in the Davis Cup final against France next month.
The second seed went down 7-6 (8-6) 6-2 to the world No. 34, whose reward is a quarterfinal against 2006 champion Davydenko.
Djokovic had arrived courtside wearing a Halloween outfit, the ATP website reported, but the 23-year-old could not keep up his performance.
"I have to congratulate him, because he really played, I think, a perfect match," Djokovic said.
"I don't think I've played bad. Actually, I think I even returned well in the first set. But any time I needed a point when it was important, he came up with a huge serve. All credit to him, he deserved to win."
Llodra is France's fourth-ranked player behind Jo-Wilfried Tsonga, Monfils and Richard Gasquet, and was coy about his hopes of being picked by Davis Cup captain Guy Forget.
"I showed I was able to beat Djokovic. I showed I was reliable. Now, in Serbia, the match will be completely different with a different surface, but I was able to show our captain that he could count on me."
Top seed Federer had no such problems as he crushed unseeded Czech Radek or Radek Stepanek 6-4 6-3 in the day'sd penultimate match.
The Swiss world No. 2 could face fourth-ranked Andy Murray in the semifinals if he beats Melzer.
British third seed Murray progressed into the last eight with a 7-6 (8-6) 3-6 6-3 win over Croatian No. 13 Marin Cilic, being taken to three sets for the second successive match.
Murray will next play Monfils, who was last year's losing finalist.