Roger Federer's quest for his 100th career title got off to a rocky start in London.
A frustrated Federer belted a ball into the stands incurring a code violation for ball abuse and later admonished chair umpire Damian Steiner with the silent treatment saying "I'm not talking to you."
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Taking the ball earlier and serving-and-volleying at times, Kei Nishikori surprised Federer, 7-6 (4), 6-3, in the Lleyton Hewitt group of round-robin play at the Nitto ATP Finals.
Nishikori took the initiative in snapping a six-match losing streak to Federer.
Running around his backhand return, Federer plastered an inside-out forehand that would have given him double-set point, but Nishikori flicked back this bit of backhand brilliance.
Federer slapped a ball into the seats in frustration then lost the plot on his forehand in the tie break.
"It was great to win and obviously the first match is not easy," Nishikori said. "Both of us were out a little bit the first set. But the second set I played better."
Attacking his forehand with more ferocity, Nishikori asserted his aggression to turn the tide against the six-time tournament champion.
"I had to change something for sure. I lost to him twice in the last two months," Nishikori said. "I tried to play a little bit more aggressive with my forehand and put a little bit of more pressure. Some moments there were some lucky points but I played well today."
Photo credit: @ATPWorldTour