LONDON: For a man standing six-foot-eight, the 13 aces Kevin Anderson sent down against Dominic Thiem could perhaps be expected on the reasonably quick surface being used at the ATP Finals.
What was more surprising, at least to those in the 02 Arena crowd on Sunday who had not seen the 32-year-old close-up before, was the agility the South African displayed in posting an impressive victory on his tournament debut.
Try as he could with his punishing baseline game, Austrian Thiem struggled to knock Anderson off balance in a 6-3 7-6(10) defeat in their opening round-robin match in a group named after one of the game's most nimble movers Lleyton Hewitt.
In actual fact it was Anderson who often launched counter-attacks from deep in the corners to surprise an opponent he has now beaten seven times in nine meetings.
Asked about his surprising mobility, this year's Wimbledon runner-up said it was something he had identified as the key to reaching the top of the game from an early age.
"My dad, who taught me growing up, was very insistent and he had great foresight to see where the game was going," Anderson, the first South African to qualify for the ATP's elite eight-man year-ender since Wayne Ferreira in 1995, told reporters.
"We spent a lot of time working on my movement from the baseline. That's what I feel more comfortable with. As my career got on, I've been trying to find ways to come forward more.
"But especially in today's game, there's a lot of times where guys are playing such great defence that you do find yourself in rallies. I spent a lot of time in my training, both on and off the court, working on my movement."
Anderson's win meant he equalled his record haul of 46 match wins in a season set in 2015 when he first broke into the world's top 10 before a succession of knee, shoulder and ankle injuries saw him slide to 80 in January 2017.
One of the game's late bloomers, world number six Anderson believes he is still improving.
"If I look at my game, I definitely feel there's some areas that I can continue to get better on," he said.
"Sometimes when you're always looking for ways to improve, you don't trust what you already have. I feel like I'm having a much better balance with that.
"I still feel like some of my best tennis is ahead of me.
"Guys are playing much better into their 30s, it changes the perspective," Anderson added. "You see Roger (Federer) play so well at, you know, (at) 37, whatever he is right now.
"That definitely changes the dynamic quite a lot."
(Reporting by Martyn Herman, editing by Pritha Sarkar)