Six-time champion is expected to book her place in the final but is refusing to take lightly an opponent who has already beaten defending champion Stephens
Serena Williams still has 'a really long way to go' to win US Open as semi-final against Anastasija Sevastova beckons
Serena Williams may be the overwhelming favourite to reach the US Open final on Friday, but the 23-time grand slam champion insists she is not looking beyond last-four opponent Anastasija Sevastova.
Williams, 36, is two wins away from an unprecedented seventh title in New York and a record-equalling 24th major title. The American's immediate challenger is 28-year-old Latvian Sevastova, who earned her place in the semi-finals with an impressive straight sets win over defending champion Sloane Stephens.
Despite 19th seed Sevastova's fine form at Flushing Meadows which also includes a win over seventh seed Elina Svitolina, Williams is heavily fancied to book her place in the final.
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Williams has never faced Sevastova before but is familiar with her opponent's tactical, all-round style of play.
"I've seen her play a lot. She's been playing really well for actually a long time. So obviously I know her game really well. She clearly knows mine," said Williams, the 17th seed.
"She's definitely someone that gets a lot of balls back and something I have to be ready for."
Sevastova, who retired in 2013 for nearly two years because of back and muscle issues, has impressed since her return and picked up the third title of her career with a win at Bucharest this year.
Despite being two wins shy of what years ago would have seemed like an improbable title, Sevastova refuses to look beyond her semi-final battle.
"I don't look that far ahead. I mean, there is still semi-finals," she said. "I was also two times in the quarters and I also didn't look ahead. It's still long way to go, I think. The grand slams are so long."
Wimbledon runner-up Williams, who returned to the sport in March after giving birth last September, is also trying to keep thoughts of how close she is to matching Australian Margaret Court's all-time grand slam record out of her mind.
Williams beat Czech Karolina Pliskova in the quarters, marking her first win over a top-10 player since she returned to competitive tennis.
"I'd been a couple steps away at the last grand slam, so I'm definitely not ahead of myself," said Williams, who fell to Angelique Kerber in the Wimbledon final.
"I still know that no matter whether I'm in the semi-finals or the finals, I have a really long way to go to win. Again, that proved to be true at Wimbledon."
In the other semi-final, last year's finalist Madison Keys will take on Japanese 20th seed Naomi Osaka.
American Keys, the 14th seed, leads Osaka 3-0 in head-to-head and won their most recent match in straight sets in the third round at Roland Garros in June.
"I think we play similarly," Keys said of facing Osaka. "I think power, obviously a big serve. I think I probably have a little bit more spin on the ball, but I think she takes time away really well.
"I don't think we will have tons of long rallies."