Serena Williams reaches US Open semi-finals with win over Karolina Pliskova

Serena Williams passed her toughest test so far at the US Open to beat Karolina Pliskova and reach the semi-finals for a ninth consecutive time.

Williams, seeded 17th, won 6-4 6-3 against the Czech eighth seed.

The American, 36, is seeking her first Grand Slam trophy since giving birth to daughter Olympia last September.

If she wins it would be her 24th major title – equalling Australian Margaret Court’s all-time record – and her seventh at Flushing Meadows.

Latvia’s Anastasija Sevastova, who knocked out defending champion Sloane Stephens earlier on Tuesday, waits in the last four.

Crowd helps Serena turn match around

Williams is only playing in her eighth tournament since becoming a mum, but had only dropped one set – in her last-16 match against Latvia’s Kaia Kanepi – on her way to the last eight.

However, having lost to Angelique Kerber in the Wimbledon final, there were question marks how she would fare against another high-calibre player.

After a slow start against the big-serving former number one, Williams grew into the match as she responded to some vociferous backing from Arthur Ashe Stadium.

She won eight games in a row – four at the end of the first and four at the start of the second – to help her secure victory in one hour 26 minutes.