Grigor Dimitrov has reached his second grand slam semi-final and first in three years after beating David Goffin at the Australian Open.

Dimitrov was tipped as a future star when he made the last four at Wimbledon in 2014 but it has taken longer than expected for his talent to blossom.

The 25-year-old, however, has been in excellent form in Melbourne and he now stands one win away from the final after beating Belgium's Goffin 6-3 6-2 6-4.

He was awaiting the winner of 14-time major champion Rafael Nadal and third seed Milos Raonic, who were playing their quarter-final later on Wednesday.

"I knew it was not going to be easy," Dimitrov said. "I think the first set was nerve-wracking. I felt I could play well but was not striking the ball as well as I could.

"I was a bit passive but with each point I was feeling a bit better and I was finding my groove. I'm just so happy right now."

Dimitrov looks finally to be fulfilling his potential after a disappointing two years, during which his ranking dropped to 40th and his commitment came under scrutiny.

Now ranked 15th, Dimitrov has a very real chance of making the final at Melbourne Park and winning his first grand slam title.

"The past two years have been a tremendous rollercoaster for me but I'm happy with the way things happened," Dimitrov said.

"I understand myself better and I'm appreciating this better now. To be in the semi-final means too much to me right now."

Goffin was playing only his second grand slam quarter-final and and the 26-year-old struggled with his serve, conceding six breaks, including three in the second set.

"His improvement is mentally," Goffin said.

"Last few months he proved that mentally he was much better than in the past. He didn't give any points. He was really solid."