Victoria Azarenka continued her remarkable winning run at the Qatar Open by knocking out 2014 runner-up Angelique Kerber in straight sets in the first round on Monday.
The Belarusian won this event in 2012 and 2013, but had to withdraw with a foot injury last year.
With defending champion Simona Halep having withdrawn from this year's event with fitness concerns of her own, Monday's first-round clash between wildcard Azarenka and eighth seed Kerber presented both with a chance to fire a warning signal to the rest of the field.
And it was Azarenka who made the most of that opportunity, cruising to a 6-0 6-3 victory in little more than an hour in her first match since teaming up with new coach Wim Fissette.
Azarenka - whose winning run at the WTA Premier event (Premier 5 for her first two titles) now stands at 11 - dropped just nine points as she stormed to the first set and, aside from a break point midway through the second, faced little resistence as she marched into round two.
"I'm pretty happy with it," she said. "You know, there are not a lot of things to complain about, but I always try to look at things that I can do better or just stay more consistent.
"I felt like, especially in the first set, I really stepped with the right attitude, with the right game plan and really executed it well.
"And the second set, I knew she was going to fight back and for me it was important to just stay consistent and stay in the moment, still stay in command.
"I feel like at 3-3 I've done that. I really took the game into my own hands again and finished pretty strong again."
Venus Williams had to come from behind to get the better of compatriot Casey Dellacqua 3-6 6-2 6-1, while Flavia Pennetta also fell behind on her way to beating Svetlana Kuznetsova 3-6 6-4 6-2.
Seventh seed Williams will now meet Barbora Zahlavova-Strycova in the second round after the Czech defeated Sabine Lisicki 7-5 6-4.
Pennetta's reward for beating Kuznetsova is a meeting with fourth seed Agnieszka Radwanska.
In the day's remaing match, Lucie Safarova progressed past Sam Stosur 7-6 (7-3) 6-4 and will now face Ekaterina Makarova.