Novak Djokovic struck first with a break in the opening game to tee up what turned into a 6-4, 7-6(4) defeat of Stefanos Tsitsipas on the fast hardcourt of the ATP Finals on Monday.
The Serb credited his quick start with revving up his momentum as he defeated his Greek rival in just under one and three-quarter hours in his opening round-robin match at the eight-man end-of-season spectacular.
“The early break was very important,” the 21-time Grand Slam winner said, “It really boosted the confidence.
“We all knew this would be a tough, tight match. We;ve had a few close matches recently (three matches since October).”
Djokovic improved to 10-2 over Tsitsipas, winning his ninth match in a row in the series.
The 35-year-old stands 14-1 in opening round contests at the season wrapup event.
“It was important to start well,” the winner said. “I only faced a break point in one game, when I had two double-faults.
“I played a great tiebreak and was solid all the way through.If you are serving well you can get a lot of free points on this court, the altitude makes it faster.
“Tonight, the first game was key, then I was able to hold my nerve.”
The competitor who has been in 15 of the last 16 editions of the Finals, holds five titles; he claimed his last in 2015.
“There is no clear favourite here,” Djokovic said. “We are all hitting the ball very well.
“I’ve jjust got to be at the top of my game.”