Sixth seed Davydenko cruised past Germany's Benjamin Becker 6-2, 6-1 at the Bercy arena but seventh seed Verdasco was made to dig deep against Italian Andreas Seppi before eventually prevailing 6-7 (3/7), 6-4, 6-4.

French defending champion Jo-Wilfried Tsonga remained in the hunt for a place at the Nov. 22-29 event in the English capital, however, with a 6-1, 7-5 win over Spain's Albert Montanes.

Tsonga, who booked his place in last year's Tour finals by winning here, romped to the first set in just under 22 minutes.

He encountered stiffer resistance in the second before grabbing the decisive break in the 11th match when Montanes double-faulted and went on to seal a 62-minute victory with a forehand winner. "I have to win the tournament to qualify, as long as Verdasco doesn't make the final," said Tsonga, the eighth seed.

"If I get to the final and Verdasco is there, I'll try to win it anyway!" added Tsonga, who next plays compatriot Gilles Simon after he prevailed in three sets over Croatian Ivan Ljubicic.

Tsonga is one of three players, alongside Robin Soderling and Fernando Gonzalez, who still have a chance of pipping Davydenko and Verdasco in the race to London but all three need to at least reach the Paris final to do so. Six of the world's top players have already secured their places and Davydenko and Verdasco, who currently occupy the last two qualifying spots, are the hot favourites to join them.

"I need to win all the matches I can to qualify for myself and not wait to see how other players do," said Verdasco. "It was my big challenge for this year and this week is the last week. After this, everything will be decided. So I'm giving my best in the last week to try to do it."

Verdasco's victory means that Czech Radek Stepanek and Croatia's Marin Cilic can no longer qualify for the season finale, but Cilic will have the chance to exact swift revenge on Verdasco if he comes through his second-round match against Polish qualifier Lukasz Kubot.

Davydenko, meanwhile, will next face either ninth seed Soderling of Sweden or Croatia's Ivo Karlovic.

"It's a good feeling," said Davydenko. "With everyone here, (Roger) Federer and (Novak) Djokovic, it's a very tough draw and it's not so easy for Tsonga or Soderling or Verdasco to reach the final and win the tournament."

Chile's Gonzalez begins his campaign against big-serving American John Isner on Wednesday, when top seeds Federer, Rafael Nadal, Djokovic and Andy Murray will all be in action.

World number one Federer faces Frenchman Julien Benneteau, a 4-6, 7-5, 6-3 victor over Germany's Philipp Petzschner, while Nadal will take on his Spanish compatriot Nicolas Almagro, who defeated Swiss Marco Chiudinelli 6-2, 6-4.

French qualifier David Guez, the world number 179, will meet countryman Gael Monfils after shocking world number 21 Stanislas Wawrinka 6-3, 6-4 in their first-round encounter.

Federer and Nadal form part of a star-studded draw in the 2.75 million euros final Masters tournament of the year, with injured American Andy Roddick the only absentee from the world top 15.