Five fight for women's top spot

CINCINNATI - With sidelined Serena Williams about to have a baby, five players have a chance to grab the women's world No 1 ranking at this week's US Open tuneup event in Cincinnati.

Williams, a 23-time Grand Slam champion who announced her pregnancy and the end of her season in April, owned top spot for 186 consecutive weeks through last September, matching Steffi Graf for an Open-era record, and traded the spot with Germany's Angelique Kerber earlier this year.

Defending Cincinnati champion Karolina Pliskova became No 1 five weeks ago but will lose points from her title run, opening the door for rivals to overtake her.