Cramps all over his body early into his Round 1 game on Monday did not stop Andy Murray from claiming the first round of the US Open.

Murray beat Robin Haase 6-3, 7-6 (6), 1-6, 7-5 in an afternoon match even as cramps hounded him while the third set ensued, CBS Sports said, adding that he occassionally held his hamstring after serves. 

"When it starts to kind of go everywhere, you don't know exactly where it's going to creep up next... When you stretch one muscle, something else then cramps, too," the 18th seeded player said, as quoted by the report. The cramps first occurred in the back of his left shoulder, then went to his forearm. 

"Cramping in my left forearm?" he asked, also quoted by CBS Sports. "I mean, I didn't use my left forearm a whole lot today." 

He felt confident the cramping won't happen after good training sessions in the much worse conditions of Miami and wondered if his nutrition was wrong, the report said. Murray's serves were affected, it also noted. Good thing the 70th-ranked Haase had a bunch of unforced errors. 

Per Reuters UK, among the other games in the men's division were: Stanislas Wawrinka (winner ) and Jiri Vesely; Tommy Robredo (winner) and Edouard Roger-Vasselin; Peter Gojowczyk (winner) and Benjamin Becker; Milos Raonic (winner) and Taro Daniel; Jo-Wilfried Tsonga (winner) and Juan Monaco. The fabled Nick Kyrgios--of Rafael Nadal-Wimbledon fame--beat Mikhail Youzhny, it added. 

Meanwhile, CBC Sports said, Maria Sharapova, world No. 5, returned with a bang after missing last year's action due to an injury. She beat Maria Kirilenko, her former doubles teammate.

According to the New York Times, in the athlete's first appearance since 2012, she performed below what she could do, but she shook all the dust off with 10 straight wins and an easy 6-4, 6-0 in 90 minutes.

"I thought there was a few times I could've broken her at the beginning of the match," Sharapova said, as quoted by NYT. "But she started off playing well and solid, and despite not taking those opportunities in a couple of those first-service games, I felt pretty good, especially toward the end of the match." 

Caroline Wozniacki of Denmark, 10th ranked, advanced 6-1, 3-6, 2-0 after Magdalena Rybarikova of Slovakia was forced out by a left hip injury, CBS Sports added.

Venus Williams also beat Kimiko Date-Krumm 2-6, 6-3, 6-3, the report added. Williams' fellow American, Sloane Stephens, advanced as well by beating Annika Beck. Simona Halep, second in the world, won 6-7 (2), 6-1, 6-2 against 20-year-old Danielle Rose Collins, who gave her a tough fight.

Angelique Kerber beat Ksenia Pervak, Reuters UK said. Others who've seen action are Belinda Bencic (winner) and Yanina Wickmayer; Kurumi Nara (winner) and Aleksandra Wozniak; and Zheng Saisai (winner) and Stefanie Voegele.