Andy Murray afforded himself a wry smile in his US Open first-round victory, such was the world number two's dominance over Ernests Gulbis at Flushing Meadows.

On the eve of the fourth grand slam of the year, Murray insisted his no-nonsense approach left him no time to cheerful on court.

But as one of his perfectly legitimate serves was inexplicably called out during his routine 7-5, 6-3, 7-5 victory over the Latvian, even the frosty could see the funny side.

While Murray's performance was typically workmanlike, Gulbis was still an opponent not to be taken lightly, his world ranking of 95 belies his undoubted talent.

Gulbis had been comprehensively beaten by Murray in each of their three previous encounters, but that unfavourable record did not seem to faze him in the early exchanges.

But it was Murray who drew first blood in the opening set, breaking Gulbis in game six as the Latvian's ground strokes momentarily eluded him.

Gulbis was up for the fight however, and he broke straight back with a series of blistering shots, it was clear it would not be all plain sailing for Murray.

But at 6-5 down and serving to stay in the set, Gulbis buckled under the pressure. He made three consecutive errors to hand Murray three set points and while he saved all three, the Scot still found enough to clinch the set.

Murray went into overdrive a the start of the second set and raced into a 3-0 lead, and while Gulbis managed to break back and restore the scores to 4-3, he let his guard down and the Scot swung the momentum in his favour once more.

And at 5-3 and serving for the set, he was in mood to surrender his advantage and promptly took a two-set lead before claiming the crucial break in game 11 in the third to seal a comfortable win.