|Dates: 23 July-8 August Time in Tokyo: BST +8|
|Coverage: Watch live on BBC TV, BBC iPlayer, BBC Red Button and online; Listen on BBC Radio 5 Live, Sports Extra and Sounds; live text and video clips on BBC Sport website and app.|
Great Britain's Andy Murray and Joe Salisbury beat Nicolas Mahut and Pierre-Hugues Herbert to reach the second round of the men's doubles.
The British duo produced an impressive performance to knock out the second seeds 6-3 6-2 in one hour 15 minutes at Tokyo's Ariake Tennis Park.
Jamie Murray and Neal Skupski also progressed against Argentina's Andres Molteni and Horacio Zeballos.
However, Heather Watson went out in the first round of the women's singles.
The only British competitor in the draw was beaten 7-6 (7-5) 6-3 by German Anna-Lena Friedsam in one hour 49 minutes.
"It definitely wasn't my best tennis but I gave it my best with what I had," said Watson. "It just wasn't enough.
"There were too many unforced errors that came and went in waves. I am just very disappointed with the outcome.
"I did everything I could to prepare right and I literally could not have done any more. I felt really good going out there."
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Murray and Salisbury face German pair Kevin Krawietz and Tim Puetz in the next round.
"I think we have the potential to be a really good team," said Murray, who begins his singles campaign against Canadian ninth seed Felix Auger-Aliassime on Sunday.
"We were well deserved winners today - we created lots of chances - but not every doubles match is like that.
"If we keep the same sort of attitude and everything, prepare diligently, I think we've got a chance of doing well."
Jamie Murray and Skupski had to come from a set down to beat Molteni and Horacio Zeballos in a final-set tie-break, winning 6-7 (3-7) 6-4 13-11 in two hours, 11 minutes.
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