Handed the chance to put another dent in Roger Federer's armour on Tuesday, Andy Murray was swiped to one side as their eagerly anticipated round robin clash at the ATP World Tour Finals turned into a Swiss romp.

Federer often struggles against the mercurial Scot, except when it really matters, most notably in their two Grand Slam finals, but he was supreme at the O2 Arena, dropping just eight points on his serve in a 6-4, 6-2 drubbing.

In bagging his second easy win, the 29-year-old former world number one, bidding for a record-equalling fifth title at the season-ending event, will qualify for the semi-finals depending on the result of Tuesday's late Group B match between David Ferrer and Robin Soderling.

"I think if you play many times against each other, you can't go the distance every single time," a charitable Federer told reporters after improving his career record against Murray to six wins in 14 meetings.

"Maybe he'll just need a feel good talk or just a nice dinner. That should do the trick," Federer said when asked how he felt Murray would respond to a chastening 76-minute loss in front of 17,000 fans.

"Tennis is not rocket science. It's pretty straightforward. I think he's going to turn around and come back and play a real good match in the next round," he added.

Maybe a chat with former Argentine soccer great Diego Maradona, again a spectator at the O2, would enliven the Scot who produced a performance barely recognisable from the one which humbled Federer in last month's Shanghai Masters final.

Federer was clearly expecting a tougher test like last year here when he prevailed in three extremely high quality sets before bowing out to Nikolay Davydenko in the semi-finals.

"I'm surprised I was able to beat Andy here because playing him in London should be really a tough," Federer said.

"I was just surprised the amount of errors he was making early on," he added.

After the rock-show lighting and ear-splitting introductions as the players warmed up the stage appeared set for a classic but like the majority of the matches so far here the fireworks failed to materialise.

No fault can be attached to Federer for that as he executed everything with precision timing and effortless power. Murray on the other hand simply unravelled.

The world number five was lucky to escape from his opening service game but he was broken to love two games later -- prompting a change of shirt colour from white to black.

Only when Murray reached 0-30 as Federer served at 5-4 did he have a chance, but that chink of light was snuffed out as the Swiss reeled off three points with a nonchalant smash, a forehand winner and crunching volley before Murray shanked a forehand wide on set point.

Federer then blazed 4-0 ahead in the second set as he demonstrated just why he has 16 grand slam titles and Murray is still chasing his first. He was simply unstoppable.

Luckily for Murray the round robin format of the event featuring the world's top eight men means he can still reach the semi-finals. He will have to dust himself down quickly before taking on Spain's Ferrer in his final group match on Thursday.

"I got off to a bad start in both sets, which doesn't help," a glum Murray told reporters just minutes after walking off court.

"I returned poorly, served poorly. Against him, that's not going to win you the match," he added.

In the day's early doubles match Wimbledon champions Juergen Melzer and Philipp Petzschner revived their hopes of reaching the semi-finals with a narrow Group A victory over Leander Paes and Lukas Dlouhy.

World number one Rafael Nadal is back in action on Wednesday against Novak Djokovic.