Maria Sharapova and Madison Keys punctuated Doha defeats with Dubai withdrawals.

Both Sharapova and Keys have withdrawn from next week's Dubai Duty Free Tennis Championships, while reigning Roland Garros champion Jelena Ostapenko has joined the field.

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Sharapova has pulled out citing a strained forearm, while an illness prompted Keys' withdrawal.

"Unfortunately both Maria Sharapova and Madison Keys have regretfully had to withdraw from the Dubai Duty Free Tennis Championships due to injury and illness," tournament director Salah Tahlak said. "We are sorry that neither Maria nor Madison will be able to play in Dubai, but we still have one of the strongest fields ever assembled for the WTA event. Maria said that she is very sorry she cannot be here and hopes to come back next year. We wish her and Madison a speedy recovery."

Keys looked listless as compatriot CiCi Bellis dispensed a bagel in the final set of her 2-6, 6-3, 6-0 Doha defeat yesterday.

The 30-year-old Sharapova, who opened the season reaching the Shenzhen Open semifinals, suffered her second straight loss falling to 92-ranked Romanian qualifier Monica Niculescu in her Doha opener.

Sharapova committed 52 unforced errors, including 11 double faults, suffering her second straight loss following a 6-1, 6-3 setback to Angelique Kerber in a clash of former world No. 1 players at the Australian Open.

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