* Frenchman beats Hewitt in final
* Mahut wins second ATP title after claiming his first last month (Adds quotes)
July 14 (Reuters) - Frenchman Nicolas Mahut won two matches in a day to capture the Hall of Fame Championship at Newport on Sunday, denying former world number one Lleyton Hewitt his first title in more than three years.
Mahut, who won his first career ATP title in the Netherlands last month, added a second in quick succession after a marathon day in Rhode Island.
He beat American Michael Russell 6-2 6-2 in their rain-delayed semi-final in the morning then returned to the grass court to defeat Hewitt 5-7 7-5 6-3 in the afternoon final.
"When you want to win a final, everything can happen. I just can't believe it's true," Mahut told reporters.
"A month ago I was playing to make the cut for the qualies (qualifying) at the U.S. Open, I was (ranked) 240 with some points to defend.
"I told my coach, I have to play great on grass to make the cut for the qualies. A month later I have two titles."
Hewitt, bidding for his first singles title since he beat Roger Federer in the final at Halle in June, 2010, also played in the morning, blunting the booming serve of twice defending champion John Isner to win 5-7 6-2 6-4.
Despite spending more than an hour longer on court in his semi-final, the Australian looked to be on the verge of a straightforward victory in the final.
The 32-year-old Hewitt won the opening set then served for the match at 5-4 in the second set but was unable to close it out as Mahut, a runner-up in Newport six years, fought back.
Mahut, 31, won the next three games in a row to force the match into a third set and despite going down an early break, he recovered and went on to seal victory after two hours and 20 minutes.
"If I could've had a day off and come back and played the final, I reckon things would've been different," Hewitt said.
"All in all it was a good week. Can't do much about it. I had the tougher side of the draw, with the semi-finals this morning, I paid the price for that." (Reporting by Julian Linden in New York; Editing by Sonia Oxley)