Simona Halep has got her WTA Championships campaign off to a winning start by seeing off Madison Keys in straight sets.

The world number four took the match 6-2 6-4 in a time of 70 minutes to earn a place at the top of the Red Group standings in Singapore.

Halep held throughout the opening set and managed to break her opponent in the third and fifth games, allowing the Romanian to cruise into a comfortable lead.

Keys struggled to hit back in the second, failing to hold once again in the fifth game as Halep pushed towards victory, though the 21-year-old did temporarily recover to level at 4-4.

In a battle of wits from that point on, Halep found the key ninth game plain sailing as she put distance between herself and her American opponent to make a winning start to the end-of-season tournament.

Dominika Cibulkova and world number one Angelique Kerber are due to face off on Sunday afternoon in the other Red Group tie.