Roger Federer said he was glad to bring down the curtain on a difficult season and hoped to bounce back for a tilt at the Grand Slam record next year.

The defending champion battled a back injury as he went down in three sets to Britain`s Andy Murray, ending his campaign for a fifth Masters Cup title at the group stage.

The 27-year-old Swiss, who also lost his five-year Wimbledon crown and the number one ranking this year, looked ahead to next season when he is chasing Pete Sampras`s record of 14 major titles.

`It`s been a good year, you know. But tough to start off with. Tough to end,` he said.

`So obviously a little bit of mixed feelings. But I think it gives me the opportunity to start over all new again next year.`

Federer failed to reach the eight-man event`s semi-finals for the first time in seven straight appearances, but he showed enough form -- and grit -- against Murray to suggest Sampras`s mark is reachable.

The former number one started brilliantly before the back injury came into play, but still toughed it out saving seven match points in a thrilling last set.

`I don`t quit once I step on court. Guess you got to drill me one in the eye, then maybe. But otherwise I don`t quit,` he said.

Federer, who was also hit by a stomach bug this week, hoped he could recover in time for January when he will target the magical 14th Grand Slam at the Australian Open.

`I`m happy the season is over. Hope I can recover from all of what happened this week because it was tough, so we`ll see how I`ll feel next year again,` he said.

Murray, who had already qualified for the semi-finals, said the win would give him a significant mental boost as he goes in search of Britain`s first Grand Slam title since the 1930s.

`Psychologically a win like that is going to be huge for me next time I play him, especially in big matches,` Murray said.

`A win against him in a match like that is similar to winning the Masters Cup. He`s one of the greatest players of all time, so it meant a lot for me to win that one.`

He also suggested Federer was far from done despite enduring his toughest season since reaching the number one ranking in 2004.

`He`s still playing great. I mean, he`s number two in the world. Nadal`s had one of the best years in tennis over the last 20 years and he`s still not that far behind him,` Murray said.

`He`s maybe lost a few more matches than normal, lost to guys that he doesn`t normally lose to. But it`s not totally surprising. I mean, he`s normally losing like seven matches a year, which is ridiculous.`

Murray faces Nikolay Davydenko later while Novak Djokovic plays Gilles Simon in the semi-finals of the 4.45-million-dollar tournament.