Serena Williams acknowledges the crowd after defeating Karolina Muchova at the US Open on Friday. Photo: Sarah Stier/AP

NEW YORK – Serena Williams moved another step closer to a record-tying 24th career Grand Slam title with a comfortable 6-3 6-2 victory over Czech Karolina Muchova on Friday to reach the last-16 at the US Open.

Wimbledon quarter-finalist Muchova held serve for an early 3-2 lead in her first career meeting with Williams.

But the six-times champion cranked up the pace and won the next seven games to take over the match.

Williams took advantage of a poor serving performance by Muchova and broke her opponent five times, including in the final game, where she sealed the victory with when the Czech sent a backhand long.

Up next for Williams will be Croatian 22nd seed Petra Martic, who beat Latvian Anastasija Sevastova earlier on Friday.

Meanwhile in the men’s draw, Alex de Minaur reached the second week of a Grand Slam for the first time after he produced an inspired performance to upset seventh seed Kei Nishikori 6-2 6-4 2-6 6-3 in the US Open third round.

The 20-year-old Australian was in control from the outset, going up a double break in the first set and leapt in the air and pumped his fist when the Japanese sent a forehand into the net on match point.

De Minaur, nicknamed “the demon”, was delighted to notch up his first win over a top 10 player.

“The crowd support was amazing,” said De Minaur, who won last month’s Atlanta Open for his second ATP title.

“I had a bit of a thrill last year against (Marin) Cilic,” he said, referring to his heartbreaking five-set loss to the Croatian in New York.

“Was two-sets-to-love up again, and I’m glad I could finally get the win.”

Nishikori was far from his best, committing 60 unforced errors and seven double faults on the sun-soaked Grand Stand court.

Next up for De Minaur is either Bulgaria’s Grigor Dimitrov or Poland’s Kamil Majchrzak.