In an interview last month after a World Tennis Tour event at the Greenbrier in West Virginia, they said they had not yet decided whether they were finished competing.
Playing almost exclusively with each other throughout their 25-year careers, the Bryans captured a professional era record 119 titles, including 16 Grand Slam wins, 39 ATP Masters 1000s and the ATP Finals title four times.
Bob and Mike Bryan, the most successful doubles pair in the history of tennis, were not on the entry list for the US Open released on Wednesday, raising the prospect that the 42-year-old twins may have chosen to end their professional careers.
The Californian pair, famous for their trademark chest-bump celebration, had previously announced they would bid farewell after this year's tournament at Flushing Meadows, scene of their Grand Slam debut in 1995.
In an interview last month after a World Tennis Tour event at the Greenbrier in West Virginia, they said they had not yet decided whether they were finished competing.
"We love this life. We had a great run if this is over," Bob Bryan said.
"We're gonna sit down and if we decide to come back and play in 2021, then you'll probably see us play the US Open just to keep it going.
"If we decide to shut it down in 2021, this might be it. So who knows."
Playing almost exclusively with each other throughout their 25-year careers, the Bryans captured a professional era record 119 titles, including 16 Grand Slam wins, 39 ATP Masters 1000s and the ATP Finals title four times.
The Bryans also won Olympic gold at London 2012 and were part of the US Davis Cup-winning team in 2007, the accomplishments they have said they are the most proud of.
Mike claimed two more Grand Slam titles with Jack Sock in 2018 after Bob was sidelined with a hip injury.
Clijsters gets wild card for US Open
Three-time US Open champion Kim Clijsters received a wild-card entry in doubles to go along with the one she got for singles as she makes her Grand Slam comeback.
The tournament begins singles competition Augst 31, and doubles on September 2. The doubles fields are being cut from 64 to 32 teams for women and men this year to reduce the number of people on-site because of the coronavirus pandemic.
Clijsters and playing partner Hailey Baptiste were joined by these other pairings getting wild cards in women's doubles: Ann Li and Bernarda Pera, Christina McHale and Usue Arconada, Jessica Pegula and Shelby Rogers.
Serena and Venus Williams are not in the women's field.
Men's wild cards for doubles went to brothers Ryan Harrison and Christian Harrison, Chris Eubanks and Mackenzie McDonald, Ernesto Escobedo and Noah Rubin, and Nicholas Monroe and Nathaniel Lammons.
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