Australian Lleyton Hewitt and Max Mirnyi of Belarus won the US Open men's doubles title on Friday as they beat American Rich Leach and Ellis Ferreira of South Africa in three sets.

Hewitt and Mirnyi, teaming up for the first time, overcame the veteran fourth seeds 6-4 5-7 7-6 in one hour 55 minutes to become the first unseeded duo in the history of the Open to win the doubles crown.

"It's been an unbelievable week. It's a fantastic win. I'd like to thanks to Max for playing with me," said 19-year-old Hewitt, who became the youngest man in the Open era to win a Grand Slam doubles crown.

The Australian is also still in contention for the singles title and faces grand slam record-holder Pete Sampras in tomorrow's semi-finals.