#2 Bob Bryan
The southpaw among the Bryan twins - Bob Bryan's serve is undoubtedly the best that the Doubles game has ever had. Bob, the elder of the two by just two minutes, was forbidden from his parents in childhood from competing with his brother Mike.
While at Stanford University, Bob became the first man to complete the 'Triple Crown' of NCAA singles, doubles (with Mike) and team titles. Bob has won 116 Doubles titles (16 Grand Slam Doubles titles - 2 less than Mike). However, Bob has 7 Mixed Doubles titles to Mike's 4.
#1 Mike Bryan
Mike Bryan unlike his brother Bob, doesn't have a big serve. But he more than compensates for that by having exceptional predatory instincts which come in handy at the net. This makes him one of the best volleyers that the Doubles game has had.
The Bryans have won 16 Grand Slam titles together and are the only Doubles pair to lodge at least 1000 match wins together. The duo are the only doubles tennis players to have won all Grand Slams, all 9 ATP Masters 1000 titles, ATP Finals as well as the Olympic Gold.
An injury to Bob in the middle of 2018, meant that Mike had to pair up with another partner for the first time at Grand Slams. Mike forged a hugely successful partnership with Jack Sock and the duo won 5 titles including 2 Grand Slam titles in 2018. Mike has thus won 5 more Doubles titles than Bob and currently has 121 titles. Mike is also the current World Number 1, the oldest to be be ranked so at the 40.