The grisly details of the terrifying knife attack that turned Petra Kvitova’s life upside down almost exactly a year ago are barely comprehensible. Watching her on the practice courts at the Sparta Praha Tennis Club, it is almost impossible to detect the effects from injuries so severe some experts believed the two-times Wimbledon champion would never resume her career; she still suffers from nerve damage to her playing hand and cannot entirely clench her fist or feel two of her fingers.

Kvitova puts down her racket to take a break from back-to-back practice sessions on the indoor courts and makes her way upstairs to a small meeting room with her coach, Jiri Vanek, a kit bag slung over her athletic 6ft frame.

After a brief and cheerful exchange in Czech with Vanek, whom she hired only a few weeks before the attack, she pulls up a chair by the window overlooking the tired and rusty clay courts below. There is an air of confidence about her as she matter-of-factly discusses the next steps in her recovery before revealing the full physical and mental trauma of an attack that left her terrified to hold a racket again after career-saving surgery and a gruelling rehabilitation.

“It will probably take more than a year to get full movement back, I’m not sure,” Kvitova says. “For tennis and for life, it’s good. I’ve done everything that I could but there is still some space to improve it. I hope that with more time I will be even stronger. I am happy that [throughout the recovery] I was always looking forward to the better tomorrows.”

The tennis club is some 260km west of Kvitova’s former apartment in Prostejov in the Czech Republic – where the vicious encounter with a knife-wielding intruder posing as a utility worker on 20 December last year took place.

Kvitova has spent a lot of time since then thinking about all of the simple things that she perhaps took for granted. As she begins to unravel the events of the past 12 months, it quickly becomes apparent that she has developed a newfound appreciation for life.

The physical scars that lace her playing hand are healing; the invisible scars have taken somewhat longer. Kvitova pauses briefly, as if to replay the moments when she worked tirelessly on a five-month rehabilitation programme, before suggesting: “If I wasn’t playing tennis I don’t think I could be as positive as I am now – but it’s not pleasant to see those flashbacks. It is a time that I try to forget but I know I will never really forget what happened. This experience has shown me how hard I can work if I need to and just how much of a fighter I am on and off the court.”

Petra Kvitova faces the media only days after the knife attack. Photograph: David W Cerny/Reuters

Kvitova made an emotional return to action in the French Open in May, where she progressed to the second round, confounding the expectations of her surgeon – who had sleepless nights over her recovery – and those who had written off her career. “I did hear the rumours that I would never ever play again but I thought: ‘I will show them,’ she recalls, offering a reminder of the steely determination instilled in her by her father, Jiri.

“I was like: ‘Why are they saying this?’ It was very painful for me, it felt like they didn’t believe me. Of course, at that time, I probably didn’t know how bad it was because nobody told me – and I am happy for that now.

“My doctor [Radek Kebrle] told me that many other experts thought that I would never ever play. He didn’t want to tell me – and that was a good decision for my mental state of mind.

I did hear the rumours that I would never ever play again but I thought: ‘I will show them'

“The week after surgery I asked my doctor: ‘Do you think I could play in Wimbledon this year?’ He didn’t answer for a while and then he said: ‘We are going to work on it and blah, blah, blah.’ I understood then that it wasn’t going to be easy.”

Although the draining physiotherapy sessions are no longer part of Kvitova’s daily routine, she still vividly remembers being gripped by fear when she attempted to hold a racket for the first time only 12 weeks after four hours of emergency surgery.

Any hopes of a comeback took a hit when Kvitova realised she could not feel or grip the racket in a way that she wanted. That familiar sensation of holding a racket firmly in her hand, as she had done since she was four years old, had disappeared almost overnight.

“I had a lot of conversations with my coach [about making adjustments to my racket]. I told him that I didn’t want to change anything because if I was to change some small details I thought it would change everything. I told him: ‘I’m going to try like this, please give me time and we will see how it works out.’

“That’s how he wanted it to be as well. I am glad that we didn’t make any adjustments to my racket. Everything is the same as before … and it’s all good,” Kvitova says – and smiles with a sense of accomplishment.

Having returned to competition, she secured a fairytale comeback in only her second tournament back when she won a 20th career title at Birmingham’s Aegon Classic with a 4-6, 6-3, 6-2 triumph over Australia’s Ashleigh Barty. Kvitova lost in the second round at Wimbledon before playing through the hard court season in north America, where she reached the quarter-finals at Flushing Meadows.

Petra Kvitova with the surgeon who helped to save her career, Radek Kebrle. Photograph: Alamy Stock Photo

“Playing on the grass at Wimbledon and getting a good result in the US Open was very important for me mentally, and for my confidence,” Kvitova adds. “This year has been a rollercoaster. The beginning wasn’t very nice, so I’m really glad that it’s over. Now I can look at everything positively again.”

Even the announcement in November from the Czech police that confirmed the investigation into the attack had been shelved because of a lack of evidence, despite receiving a number of clues from the public, has not fazed her.

Detective Jan Lisicky told reporters they would “immediately start criminal proceedings” should they identify the culprit. Kvitova has shifted her focus from expecting a prosecution to regaining a position in the top 10.

“It was a pretty tough year and I had a lot of emotions during my comeback. But it has been a year [since the attack] already and I can see that I can play tennis – and I can play it well, and for me this is the best outcome I could have hoped for.”

As Kvitova gathers her belongings and prepares to resume pre-season training before her opening tournament in Brisbane in January, she adds: “I have started to live with my new hand. I’ve started to try to like it, to love it and that’s how I am going to take it. It’s my hand and I am just happy that I have all of my fingers.”

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