It took Agnieszka Radwanska 17 years to decide that her father, Robert, was not the best man to be her full-time travelling coach. It has taken the 23-year-old Pole just three months to appreciate the wisdom of her decision to stop touring with her father and to work instead with Tomasz Wiktorowski, Poland's Fed Cup captain, and Borna Bikic, who used to coach Jelena Dokic.
Radwanska's fine start to the year continued on Saturday when she claimed the biggest victory of her career, beating Maria Sharapova 7-5, 6-4 to win the tournament in Miami for the first time. It was her second title of the year following her success in Dubai and extended her remarkable record of losing to only one player in 2012, Victoria Azarenka having beaten her in Sydney, Melbourne, Doha and Indian Wells. Already at a career-high No 4 in the world rankings, Radwanska is now breathing down the neck of Petra Kvitova, the Wimbledon champion and world No 3.
"I'm just very, very happy that I have been able to play my best tennis since the beginning of the year," Radwanska said after winning the title without losing a set. "It's a great feeling to win a tournament like this here in Miami. It's the biggest tournament after Grand Slams, especially with all the top players here. You have to play six very good matches to win this tournament."
In an age dominated by baseline drones who hit the ball as hard as they can at every opportunity, Radwanska is a breath of fresh air. Her style is often compared to that of Martina Hingis, who made up for her own comparative lack of power with the inventiveness of her game.
Radwanska gave a perfect demonstration of similar qualities in condemning Sharapova to her fourth defeat in four appearances in the Miami final. The Pole's intelligent play was summed up by her serve, which she did not drop once thanks to her clever variations of pace, spin and placement.
"I really played well today, from the beginning till the end," Radwanska said. "I was really focusing on my serve. I'm very happy I didn't lose my serve. I think it was actually the key to this match. I was playing against a really good player, a top player, who is second in the world right now. I had pretty much nothing to lose. It's a great feeling to beat those kind of players, especially in the final and by playing great tennis.
"I think my tennis is just about trying to mix it up. I think I was born with that, so it's never been one shot or one thing. When we practise, we practise everything. That's what we were doing all my life, pretty much."
While Radwanska admitted there had been "some arguments off the court" with her father, she appreciates the huge part he has played in making her the player she is today. "Everything what I can do on court right now, it's because of my father," she said. "If I can do something, it's for sure because of him."
Radwanska still works with her father when she returns home to Krakow – she is one of the few top players who do not have a warm-weather training base – and he was watching her in Miami, although he missed the final because he was unable to change his flight home.
"On the court we always had a good relationship and he's a great coach," Radwanska said. "He really taught me everything and, for sure, without him I wouldn't be here on the court, but sometimes it gets too much when you mix up your private life with tennis. Professional tennis is always a lot of stress and emotions and everything. So we decided that I would just practise with him at home and travel with someone else."
Radwanska says her new coaches have simply continued her father's good work. "I think I've known Tomasz since I was 10," she said. "He was actually travelling sometimes with my dad as well, so he really knew how I was practising, what I've been doing and not doing. We've known each other for a long time, so the relationship is pretty easy. He knows what I like to do, how I like to practise."