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.
However, Heather Watson exited in the first round of the women's singles, beaten by German Anna-Lena Friedsam.
Friedsam won 7-6 (7-5) 6-3 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.