Six-time champion Serena Williams shook off a sluggish start to power past eighth-seeded Karolina Pliskova 6-4, 6-3 on Tuesday and into the US Open semi-finals. The US superstar, chasing a record-equalling 24th major title, surrendered an early break to Pliskova, but she roared back with a streak of eight straight games to put away the opening set and take a 4-0 lead in the second against the woman who beat her in the semi-finals at Flushing Meadows in 2016.

"I just wanted to play better," Williams said of her mindset as she trailed 3-1 in the first. "I was thinking, you know, I can play better, so that was the good news." Williams did indeed cut down on the errors, and came up with the big serves when she needed them. She finished the match with 13 aces and will take on Anastasija Sevastova for a place in the final after the 19th-seeded Latvian toppled defending champion Sloane Stephens 6-2, 6-3.