Roger Federer kept his hopes alive to reach the semi-finals of the end of season ATP Finals in London this evening with a straight sets victory over Dominic Thiem. Federer the six-time champion won the match 6-2 6-3 with a solid performance after his shock defeat to Kei Nishikori on Sunday which was full of unforced errors. Next for Federer on Thursday is Kevin Anderson who thrashed Nishikori this afternoon 6-0 6-1.