After a six-month hiatus from golf over alleged cocaine and alcohol abuse, Dustin Johnson appears to be back on form. On Sunday the 30-year-old claimed victory at the elite World Golf Championships-Cadillac Championships in Miami, telling reporters that fatherhood was behind his improved focus. Following his win, Johnson was greeted at the 18th hole on the Trump National Doral course by his model fiancée Paulina Gretzky - daughter of former NHL great Wayne - and their son Tatum, who was born in January. The new parents shared a passionate kiss in front of cameras, while cradling their newborn between them. Gretzky described her husband-to-be as the 'best dad' and 'best friend' she could ever wish for. Scroll down for video . Passionate embrace: After claiming victory at the elite World Golf Championships-Cadillac Championships in Miami on Sunday, Dustin Johnson was greeted at the 18th hole by his family . Doting dad: He was overjoyed to see his model fiancée Paulina Gretzky - daughter of former NHL great Wayne - and their son Tatum, who was born in January . Perfect match: The new parents shared a passionate kiss in front of cameras, while cradling their newborn between them . She continued to ABC News: 'He's been so supportive with me and we're just there for each other. I couldn't be happier for him.' Talking about how fatherhood had changed his life for the better, Johnson added: 'It's hard to describe, but just from the first day he's born, your perspective on life completely changes. 'Things that were important aren't important anymore. 'It kind of makes life a lot easier I think, just because there's just one thing that's kind of all you think about. It definitely simplifies stuff.' When Johnson announced his decision to step away from golf last July due to 'personal challenges', rumors about his lifestyle swirled, including the suggestion that he may have been suspended by the PGA Tour. Indeed, Golf.com reported that Johnson had failed three drug tests: one for marijuana in 2009 and two for cocaine, in 2012 and 2014. Johnson celebrates with Donald Trump as he holds the Gene Sarazen Cup after winning the WGC-Cadillac Championship WGC at Trump National in Doral . Career success: Johnson turned professional as a golfer in late 2007 in his early twenties . However, the Tour - which had initially said it did not comment on rumors or speculation - released a statement saying Johnson had taken a voluntary leave of absence and had not been suspended. And in a news conference on Sunday when if he had ever failed a Tour drugs test, Johnson replied: 'No. Thanks'. In a candid interview with Sports Illustrated this January, Johnson revealed that alcohol was his real vice. He said he would excessively drink and party to relieve stress, with his tipple of choice being Grey Goose, soda and lime. In a bid to get clean, Johnson said he took time out from sport and concentrated on home life. Bundle of joy: Johnson's son Tatum Gretzky Johnson was born on January 19 . Changed man: The golfer says fatherhood has helped him to put his bad boy party days behind him . Love birds: Johnson proposed to Gretzky in August 2013 - as of now, there are no reports of where and when a wedding will take place. Commenting on his time out, he said: 'I got to spend a lot of time with Paulina and help her as much as I could through her pregnancy, and then the birth of our son. 'I really enjoyed being able to be home and not having to leave or do anything. 'I was in the gym every single day, every morning, and then spend the rest of the time either I would go practice a little bit or just hanging out with Paulina.' Johnson returned to the green in Febuary at the Farmers Insurance Open in Torrey Pines. As he won big on Sunday night, the two most important people in Johnson's life were waiting for him. He concluded: 'Paulina and Tatum were waiting for me when I got done. That was the best part of the day for sure.' 'My game is in good form. I feel really confident in my golf swing. I need to do some work with the putter and short game, especially leading into Augusta.' Johnson proposed to Gretzky in August 2013. As of now, there are no reports of where and when a wedding will take place.
The new parents shared a passionate kiss in front of cameras, while cradling their newborn Tatum between them . Talking about how fatherhood had changed his life for the better, Johnson said: 'It kind of makes life a lot easier I think, just because there's just one thing that's kind of all you think about. It definitely simplifies stuff'
He took a six-month break from golf over alleged cocaine and alcohol abuse last June .