Andy Murray makes winning return, Cori Gauff knocked out at Western and Southern Open

The Scot, continuing his comeback from major hip surgery after the coronavirus pandemic lockdown, took the first set 7-6.

The 22-year-old American fought back in the second set 6-3 to level the scores going into the decider. Murray then fought back to crush his less experienced challenger 6-1 as he prepares for the US Open.

A host of dropouts have left only a handful of top seeds set to stay and compete in America's biggest tennis event of the year.

"My goal is to come in and my hip to be feeling good," said three-times Grand Slam champion Murray.

"That's what I wanted so I don't mind how much tennis I get to play, I know that will come the practice, the more matches I get but the concern for me is my hip going to be well enough," the 33-year-old Briton added.

If Murray's game showed rust his battling instincts remained sharp, particularly in the first set tie-break when he trailed 5-2 before fighting back to take control.

Tiafoe secured his only break to go up 5-4 in the second on the way to leveling the match but Murray, twice Western and Southern champion, broke the young American at the first opportunity in the third and closed out victory.

Canadian 12th seed Denis Shapovalov showed little rust in his first tournament since February as he reeled off nine aces to dispose of 2016 champion Marin Cilic 6-3 6-3.

With the win, Shapovalov, who faced just one break point over the course of the contest, improved his head-to-head record against the Croatian to 3-1.

Big-serving Canadian Milos Raonic fired 19 aces to topple Sam Querrey 6-4 6-4 and set up a second-round clash with either Dan Evans or Russian 10th seed Andrey Rublev.

The tournament lost one of its marquee names when 13th- seeded Greek Maria Sakkari dispatched Coco Gauff 6-1 6-3 to spoil the 16-year-old American's Western and Southern debut.

After a run to the Lexington semi-finals last week Gauff was put under pressure by her Greek opponent, committing 24 unforced errors and hitting only six winners.

There was a rematch of the Shenzhen final in January and another upset as Russia's Ekaterina Alexandrova toppled ninth seed Elena Rybakina of Kazakhstan 7-5 7-6(6).

Croatian 15th seed Donna Vekic was also a first-round casualty, falling 6-2 6-3 to twice Australian Open champion Victoria Azarenka of Belarus.