LONDON (AFP) – Roger Federer suffered a shock straight-sets defeat to Kei Nishikori at the ATP Finals on Sunday, severely denting his bid for the 100th title of his illustrious career.
The Swiss, who has won the season-ending event a record six times, produced an uncharacteristically error-prone and fractious display as the Japanese seventh seed prevailed 7-6 (7/4), 6-3.
The result means Federer is now in danger of failing to qualify for the semi-finals for just the second time in his career.
Federer, 37, has beaten Nishikori in Paris and Shanghai in recent weeks but despite having the backing of a full house at the O2 Arena, he never really settled into a groove.
The normally cool Swiss was warned by the umpire for ball abuse in the 12th game after Nishikori produced a staggering backhand winner down the line.
The Swiss great made 20 unforced errors in the first set and Nishikori capitalised, forcing a tie-break in which he raced to a 6/1 lead before sealing it 7/4.
Federer, showing real urgency, broke Nishikori immediately at the start of the second set but it proved a false dawn as he lost his own serve as his frustrations mounted.
Nishikori broke again in the sixth game and served out for victory.
The title is contested by the eight players who have accumulated the most ranking points over the season and is in a round-robin format, with the best four players reaching the knockout semi-finals stage.
Earlier, Kevin Anderson made an impressive ATP Finals debut in the same Lleyton Hewitt group, beating Dominic Thiem 6-3, 7-6 (12/10).
South African giant Anderson came into the match with a healthy 6-2 lead over Thiem in head-to-heads but had lost their two most recent meetings, including a straight-sets defeat at the US Open.
The Wimbledon finalist, who stands at 2.03 metres (six feet eight inches) tall, established an early grip, dominating the early exchanges and securing the crucial break in the fourth game.
