Publications
Partners
The pair hooked up in 2013 after Sharapova called off her engagement to basketball player Sasha Vujacic and they reportedly share a home in California.
World No 11 Dimitrov, 23, is widely seen as one of the new guard able to win a Grand Slam and his 27-year-old girlfriend - a five-time major champion - said all was well in their relationship.
"It's just obviously nice to have each other, and even though we have our respective careers and we train, to kind of have other's support is always nice," she told The Age newspaper in Melbourne.
"I think that he's grown so much in the few years that I've even been with him in terms of his focus and commitment to the sport.
"Obviously, I've always kind of watched his career grow from the junior days, and to be able to see him stride in the top direction really puts a smile on my face."
Dimitrov began his Australian Open campaign in decisive fashion Monday, brushing aside German Dustin Brown 6-2, 6-3, 6-2 in just 69 minutes.
Sharapova gets her tournament underway later on Monday against Croatia's Petra Martic.
