Roger Federer could not hide his disappointment after being eliminated in the semi-finals of the ATP World Tour Finals on Saturday (November 28th).

The world number one was in confident mood going into his clash with Nikolay Davydenko, having defeated the Russian in all 12 of their previous meetings.

However, Federer got off to a slow start - a problem that plagued him throughout the season-ending tournament - and eventually slumped to a 2-6, 6-4, 5-7 reverse.

"Coming so far in a tough group, in a tough tournament, I had hoped to get through to the final and maybe win again," said the 15-time Grand Slam champion.

"I was a couple of points away but just couldn't get it done. I thought he played strong throughout, even though I don't think it was our best match we ever played against each other."

The Swiss maestro added that his frustration at losing was heightened by the fact that he was feeling "better and better" as the match progressed at London's O2 Arena.

Nevertheless, Federer can look back with pride on a 2009 campaign which has seen him reach the finals of all four majors - winning two - and completing the career Grand Slam.