Playing pain-free tennis has Canada's Vasek Pospisil thinking about what might be possible on the ATP Tour's singles scene. A refreshed mindset and solid results have helped build his confidence too.

Since undergoing successful back surgery in 2019, Pospisil has displayed the form that saw him crack the top 25 earlier in his career. He recently won the Tour's comeback player of the year award and is aiming higher for 2021 as he prepares for the Australian swing.

"I feel like every week I'm a better player than I was the week before," Pospisil said. "I feel like the rate of my improvement the last 12 months has been maybe at a faster rate than ever in my career."

The 30-year-old Pospisil first started to break through in 2013 when he reached semifinals in Montreal and Basel. By early 2014, he had risen to No. 25 in the world rankings.

Pospisil won a Wimbledon doubles title that summer and made his first Tour final appearance in Washington. However, back woes also became a problem that year.

Somewhat compromised physically, Pospisil had a few mediocre seasons before the back issues finally became too much in late 2018.

Pospisil decided on surgery to repair a herniated disc and missed over half the 2019 season. He came back at Wimbledon but didn't feel like himself on court until playing in Shanghai that fall.

"That was when I felt like, 'Wow, OK I'm back playing really great tennis,'" he said in a recent interview. "I think Davis Cup (afterwards) just kind of confirmed it and gave me that little bit of extra confidence, that confirmation that showed the consistency of my level of play."

Ranked 148th at the start of last year, Pospisil climbed to No. 61 by season's end.

The Vancouver right-hander reached the final at the Open Sud de France before the pandemic started, and matched the feat in November at the Sofia Open in Bulgaria.

"I think a lot of that goes to just feeling really healthy on the court, working with a great team right now, and also just having a different perspective on life and the sport," he said from Bradenton, Fla. "I'm much more relaxed so I think I'm able to process information better.

"I just feel like I'm playing the best tennis of my career right now."

In preparation for the 2021 campaign, Pospisil recently spent a couple weeks training with good friend and world No. 1 Novak Djokovic in Belgrade. Pospisil was originally in the field at this week's Delray Beach Open but instead will shift focus to playing Down Under.

The Australian Open is set to begin Feb. 8 at Melbourne.

"I'm not setting any limits for myself," Pospisil said. "I feel like anything can happen. If I stay healthy and if I can stay fresh mentally and keep improving at the rate that I'm improving, then who knows? I think I can definitely achieve a higher ranking than my previous career high of No. 25.

"That's in the back of my mind as something I would still like to do. But I'm still just enjoying the process. I'm trying to do the best I can."

This report by The Canadian Press was first published Jan. 6, 2021.

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