Jack Sock explains improved form at ATP Finals ahead of semi-finals

Jack Sock has put his improved form down to "taking the pressure off" and "having fun on court" as he prepares to face Grigor Dimitrov in the semi-finals of the ATP Finals.

The American was the final player to seal his place at The O2 after winning the biggest title of his career at the Paris Masters.

Sock lost his opening game to Roger Federer but won his other two group games, including shocking world No 3 Alexander Zverev on Thursday, to progress from the Boris Becker Group.

The 25-year-old thinks managing his expectations in the second half of 2017 has helped him regain the form he displayed at the start of the year.

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"I think I had a hot start to the year. I won a couple titles, played deep into Indian Wells, Miami, played a lot of tennis, singles and doubles," Sock said.

"After that, I put a lot of pressure on myself, had a lot of expectations to keep that up every single week. We're all human. That's probably not going to happen unless your name is Roger or some of those guys.

"You're going to lose some matches, you're going to have some bad weeks, for sure. It's part of sport. I think I let that get me down a lot through the year.

"The last week of the year, I talked to my coach [Jay Berger] at home. We kind of said, 'screw it, take that pressure off yourself, go have fun on court again'.

"I enjoyed being on the court. With the pressure I was putting on myself, I wasn't having the fun times that I had at the beginning of the year and in the past.

"I think once I did that, I think now the tennis that I'm playing is the - the better tennis I'm playing is showing much more."

Sock's win in Paris was his third title of the year and he is the first American to reach the semi-finals of the season-ending championships since Andy Roddick a decade ago.

And while he thinks he could now go all the way to win the title, he insists his mindset will not change.

"I mean, why not?" he replied when asked if he had what it takes to go all the way.

"I played Grigor a few times. He got me early on when we played. I've been able to get some wins against him.

"But once again, I'm playing with a lot of confidence as well coming off Paris, playing here, winning some of my matches, getting into the semis.

"You never know what can happen. I'm obviously not looking ahead at all. I have a really good record against Roger. If I were to play him again... Obviously that wouldn't help me.

"No, I don't even want to talk. I'm focusing on Saturday. I'm going to go one point at a time starting in the semis."

The season-ending extravaganza ATP Finals ends another memorable year which will be covered via our website www.skysports.com/tenniswith live blogs, reports, reaction and expert analysis as the season reaches its climax.

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