Andy Murray and brother Jamie battled past French pair Nicolas Mahut and Edouard Roger-Vasselin at the Citi Open in Washington.
The former world number one has so far been restricted to doubles action since returning to the game following his hip resurfacing operation in January, and played in the mixed event alongside Serena Williams at Wimbledon.
Murray, who has suggested his singles return may be closer than he originally thought, produced a composed display alongside his brother as they progressed to the quarter-finals with a gutsy 6-4 6-7 (7) 10-5 win in a tie-break decider.
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A return to the hard courts in August appears in Murray's sights, but that could yet be delayed until after the US Open.
The 32-year-old's last grand slam appearance was at the Australian Open in Melbourne, where he lost to Roberto Bautista Agut in the first round.
Pairing with his brother was not a new partnership, the Murrays having played together at the Rio Olympics and also formed a prolific partnership during Great Britain's 2015 Davis Cup victory.
Jamie Murray, meanwhile, was looking to defending his ATP Tour title won in Washington last year with Bruno Soares.
The opening set went with serve before the Murray's pressure told in game 10 to gain a crucial break.
The match remained a tight affair as the French pair held to force a tie-break.
The Murrays saw two match point chances missed having been 6-4 up, the second with a wide return from the former world number one.
Some more fine returns from the British duo saw another opportunity to break for the match, but again the Frenchmen responded to level at 7-7 before closing out to force a 10-point tie-break decider.
Mahut and Roger-Vasselin then appeared to be in control after moving 5-3 ahead, only for the Murray brothers to respond magnificently and lead 8-5.
Jamie Murray then served for the match, with Andy's crosscourt forehand setting up another opportunity to take a hard-earned victory, which was secured when the return went into the net.