Murray, who missed last month's Australian Open after testing positive for coronavirus, was forced to dig deep to win his first-round match at the World Tennis Tournament against Robin Haase 2-6 7-6 (7-2) 6-3 in two-and-a-half hours.

"Every time I lose a match I'm getting told to retire, that I should stop playing, that I'm finished and got nothing left or whatever and it's sad and all of these things" said the 33-year-old Scot after his first tour-level win since the US Open on September 1.

"I feel like I'm playing for my career just now, each time I step on court, which is a motivation in some ways.

"But it also adds a bit of extra stress.

"There's a bit of extra doubt there and on top of that I'm playing with a metal hip, which is hard.

"Trust me, it's not easy."

Other first-round winners in Rotterdam were Kei Nishikori, 7-6 (7-4) 6-1 over seventh seed and last year's finalist Felix Auger-Aliassime, Cameron Norrie and qualifier Marton Fucsovics.

The 31-year-old Nishikori is 3-7 since returning from injury and illness in September last year and his next opponent will be an Australian, in Alex de Minaur or John Millman who play their opening round match on Tuesday.

Former world No.1 Murray, now ranked 123rd, was back on court on Monday after losing in Montpellier last week in his first ATP Tour match for four months.

Murray lost the first set to Haase in 34 minutes, saved two break points in the seventh game of the second before winning it in a tiebreaker and then sealed a memorable victory by battling back from 3-0 down in the decider.

"From the mental side yeah, I did well to win because I was really struggling with my game for probably about an hour-and -a-half of that match," he said.

"I moved pretty well and played for two-and-a-half hours and my hips and groin and stuff felt good, so that was positive.

"But from the tennis side, it was average at best."

Murray will play Russian fourth seed Andrey Rublev or American Marcos Giron in the second round.

Australian Associated Press