The 41-year-old Bryans have won a record 16 men's doubles Grand Slam titles as a pairing. They also helped the Americans win the 2007 Davis Cup.
The last time they played together for the United States was in 2016.
They have said that 2020 will be their final season on tour, wrapping up with the US Open in September.
Fritz, Opelka and Paul all are 22 years old. Paul is making his debut as a member of the U.S. Davis Cup team.