United States Grand Slam doubles record holders Bob and Mike Bryan have retired from the Davis Cup after playing in the competition for almost 14 years.
The pair, who have won 16 Grand Slam doubles titles together, announced their decision on Bob's Instagram page on Sunday while at the Australian Open.
"Mike and I want to formally announce our decision to step down from our role as active members of the US Davis Cup team," Bob wrote on the social media website.
"Clinching the Davis Cup final in 2007 while representing Team USA was one of the greatest highlights of our career."
The pair, who face American Brian Baker and his Croatian partner Nikola Metic in the third round of the doubles at Melbourne Park, were praised by the International Tennis Federation (ITF) President David Haggerty for their commitment to the team competition.
"I would like to pay tribute to Bob and Mike Bryan for the outstanding commitment, dedication and passion they have shown for the Davis Cup, our flagship men's team competition," Haggerty said in a statement.
"Since 2003, they have compiled one of the best records of any doubles pairing in Davis Cup history and helped the US lift the winners trophy in 2007.
"They symbolize what the Davis Cup is all about."
The 38-year-old twins compiled 24 victories and five losses in the 29 ties they played together and had already been awarded the ITF's Davis Cup commitment award for playing in at least 20 ties.
The US face fifth-seeded Switzerland in the first round of the Davis Cup from Feb. 3-5 in Birmingham, Alabama.