He may be the youngest player remaining in the Australian Open boys’ singles draw, but 15-year-old Stefan Kozlov is still one of the favourites to claim the title.
For someone who plays so confidently on the court, number two seed Kozlov is quietly spoken off it.
But every word from his mouth speaks volumes of a player who knows his game, and what he needs to do to improve it.
From last season, to the offseason, a wildcard to the ATP event in Newport, and even his new coach, Kozlov can identify the positives and the negatives in everything.
While doing that, he even has time to deflect the focus back home to the other two Americans in the junior top ten - Francis Tiafoe and doubles partner Michael Mmoh.
“I guess a little bit, but I don't really pay attention to it that much and I kind of just keep the spotlight on them,” said Kozlov when asked if there is much hype surrounding the three prospects in the US.
Macedonian-born Kozlov finished the highest-ranked of the trio last year, ending 2013 as the world’s fourth best junior player after a breakout season.
“I thought I had a really, really good year and I thought I could have won a lot of the matches I lost if I didn't get into certain positions,” said Kozlov of his 2013 campaign.
In 2014, Kozlov has been getting out of some of those positions – including in his first two matches at AO2014 that have lasted just minutes shy of five hours.
“The first two rounds (were) not so good, but today I played pretty well,” said Kozlov after Wednesday’s match.
After finding himself trailing 0-3 in the deciding set of his first round match, and behind again in the second round, Kozlov was quick to identify the problem.
“I lose concentration a little bit, and give a lot of loose errors and then I find myself again,” he said.
But on both occasions he did find himself, and has recovered to win.
On Wednesday, the American had his simplest match of the tournament, breezing past Russian Boris Pokotilov 6-1 6-2 in just under an hour.
It’s all part of a learning curve for Kozlov, one fast-tracked by his wildcard into the ATP event in Newport last July.
Kozlov lost to experienced Michal Przysiezny 3-6 7-6(9) 4-6 in the first round, but saved four match points before winning the second set.
“I definitely learned a lot out of that match because of how good the level was, and how good I had to be mentally.”
“I still go back to that match and think about how I need to close out matches and what I need to do in really important points,” said Kozlov.
After cramping severely and having his brother help him from the court following the match, it also highlighted the level of fitness required.
That was a focus for Kozlov in the offseason.
“I did a good amount of fitness with the USTA and with my dad privately.”
“I know I needed to improve a lot in fitness, so I did a good amount and I am still improving,” added Kozlov.
Kozlov has the bonus of working with his father Andrei at the Kozlov Tennis Academy in Florida, in addition to USTA National Coach Nicolas Todero.
It was only three years ago Kozlov linked up with Todero and the United States Tennis Association after previously working with just his father.
Training at USTA’s training centre in Boca Raton under Todero gave Kozlov a different perspective of his game, but he still gets plenty of assistance from his father.
“I think it changed a good amount, Nicolas was a player himself so that experience helps me a lot.”
“My Dad is very good so i think the mix between both is very good,” said Kozlov.
Kozlov is hoping to continue his progress in 2014, with Delray Beach Open qualifiers in February and the likelihood of more Challenger events.
But first, he still has unfinished business at the Australian Open.
On Thursday Kozlov meets Russian Andrey Rublev for a spot in the boys’ singles semi final.