LONDON -- American pair Mike Bryan and Jack Sock saved a match point in the deciding tiebreaker to beat Pierre-Hughes Herbert and Nicolas Mahut 5-7, 6-1, 13-11 for their first ATP Finals doubles title together on Sunday.

Having failed to take advantage of five championship points during the first-to-10 match tiebreaker, Bryan and Sock then had to save one against their French opponents before finally closing out victory at the O2 Arena.

"It was a hell of a match," Bryan said.

The 40-year-old Bryan has now won the season-ending tournament five times. He won four times with his usual partner -- and brother -- Bob, who has been out with an injured hip since May.

Sock and Bryan have dominated since teaming up, winning Wimbledon and the U.S. Open before finishing their season in style in London.

"It's been a hell of a ride," Bryan said. "This could be our last hoorah because Bob's training back in Florida."

After reaching the singles semifinals last year, Sock has endured a torrid season in that format, falling outside the top-100 ranked players. However, he became the first American since John McEnroe to add a doubles final appearance at the tournament to his last-four singles showing.

"This is special because it was a pretty bad year in singles," Sock said. "This makes up for some of the low moments I've had."

The French duo's season is not over yet. Herbert and Mahut are part of their nation's squad for the Davis Cup final against Croatia, which starts in Lille on Friday.