Roger Federer [Images] began his quest to win one of the few titles to have escaped his grasp in 2004 with a 6-3, 6-4 first-round victory over Czech qualifier Bohdan Ulihrach at the World Indoor Tournament on Wednesday.

The Swiss world number one, playing his first match since losing in last month's Australian Open semi-finals, overcame early jitters to chalk up his fourth successive triumph against Ulihrach.

Paradorn Srichaphan [Images], however, brought Guillermo Coria's trial on the indoor circuit to a shuddering halt in the second round. The popular Thai beat the second-seeded Argentine 2-6, 7-6, 6-3.

Ulihrach was facing a tall order when he stepped on court, the last time Federer had lost back-to-back matches was in May 2003, and that was before he became the world's best player.

"I'm at one of the few tournaments that I didn't win last year so the pressure is off," Federer joked.

"I have confidence in my own ability now and confidence is the best way to win matches."

With only seven defeats over the past 16 months, Federer safely negotiated five break points in the opening set to frustrate Ulihrach.

Uncharacteristically, it also took the top seed six set points in the ninth game before he bagged the set.

He let a 40-0 advantage slip and Ulihrach missed an opportunity to break when a backhand agonisingly bounced just wide of the sidelines.

A Federer double fault handed Ulihrach another chance to break but that too fell by the wayside. Federer wrapped up the set when his opponent misfired a ball into the crowd.

After a 73-minute workout Federer booked his place in the second round against compatriot Stanislas Wawrinka, who pulled off a shock 7-6, 6-2 victory over Frenchman Sebastien Grosjean.

DEVELOP GAME

Coria had opted to skip his favoured claycourt events in South America this month to develop his all-court game but the move did not payoff.

He succumbed in the first round at Marseille last week and failed again against the talented but often inconsistent Paradorn.

Joachim Johansson enjoyed his status as the newest member of the top-10 club with a 6-2, 6-7, 6-3 win over Taiwanese qualifier Yeu-Tzuoo Wang.

The Swede, who cracked the ATP top 10 rankings for the first time this week after capturing his second title of the year in Marseille, recovered from a second-set hiccup to win in just under two hours.

"It's always tough to go from one tournament to another without a gap so it takes time to adjust," said Johansson, who won his first title a year ago this week in Memphis.

After climbing 141 places in the standings in just 13 months, he added: "You always want to be on top and if I play the way I know I can, it can only get better but I still have to improve everything in my game."

He was in imperious form in the first set and overpowered Wang with his blistering groundstrokes.

Wang refused to be intimidated by his 1.98m tall opponent and hit back in the second when Johansson prepared to serve out for a straight sets victory.

He broke the Swede while trailing 4-5 in the set by forcing Johansson to swipe a forehand into the net before running away with the tiebreak 7-2.

The fifth-seeded Swede regained his concentration in the third to seal victory with an overhead smash.

The win set up a second-round showdown with his namesake, 2002 Australian Open champion Thomas Johansson.

Qualifier Wawrinka made a mockery of the ranking difference with Grosjean, who at number 27 is 101 places above him, with the biggest win of his professional career.

Last year's finalist Juan-Carlos Ferrero of Spain also slipped out beaten 6-4, 6-7, 6-3 by Czech Radek Stepanek.

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