Andy Murray has registered his third three-set victory in a row to progress through to the Citi Open quarter-finals.

The former world number one let slip the opening set but recovered to prevail by a 6-7 6-3 7-6 scoreline against Marius Copil, with the match in Washington ending past 3am local time.

An exhausted Murray let his emotions out at the end of another gruelling encounter, and it was a reaction which was justified after a year on the sidelines due to a hip injury.

The 31-year-old may have thought that his time at the tournament - just his third in 13 months - was coming to an end when losing seven successive points to lose an opening-set tie-break, but the three-time Grand Slam champion regained his composure.

Copil hit 20 aces during a contest which lasted more than three hours, but it was Murray who prevailed 7-4 in a final-set tie-break played in front of a sparse crowd.

Murray will now hope to recover in time to face Australian youngster Alex de Minaur, which that match expected to start around 9.30pm local time on Friday.

There was also success for British number two Cameron Norrie, who reached his second ATP Tour semi-final in a row with a win over Adrian Mannarino at the Los Cabos Open.

However, Heather Watson bowed out at the last-16 stage in San Jose, losing out 6-4 4-6 6-0 to Venus Williams.