World number one Simona Halep eased into the third round of the French Open with an emphatic straight-sets victory over Taylor Townsend.

Halep had to come from a set down to beat Alison Riske on Wednesday in an encounter which was put back due to rain, but had no such trouble in a 6-3 6-1 thrashing of Townsend.

Last year's runner-up maintained the momentum gained from her first-round fightback, breaking five times in a dominant performance on Court Philippe Chatrier.

The 72-ranked Townsend hung in there, but she was no match for Halep, who will take on Andrea Petkovic after coming through two matches in as many days as she eyes a first grand slam title.

The top seed worked Townsend from side to side with powerful groundstrokes from the off, breaking in the first game of the match and taking a 3-0 lead when the southpaw drilled a wild forehand long.

Halep showed great intensity and a bagel looked to be on the cards until the American warmed to the task, getting on the board to make it 4-1 as she mixed up her approach effectively.

The crowd were appreciative of a perfectly executed Townsend backhand drop shot as she broke back and saved four set points before Halep wrapped it up with an 11th winner.

Halep pumped her first as she marched back to her chair and was well on her way to victory when she broke to go 3-1 up in the second, Townsend looping a backhand beyond the baseline after Halep blasted a forehand beyond her.

Townsend was unable to hold up Halep, who wore down her tiring opponent and broke again for a 5-1 lead before holding to love to advance in 68 minutes.

STATISTICAL BREAKDOWN  
Halep [1] bt Townsend 6-3 6-1

WINNERS/UNFORCED ERRORS  
Halep – 21/13
Townsend – 9/16

ACES/DOUBLE FAULTS  
Halep – 2/0
Townsend – 1/2

BREAK POINTS WON 
Halep – 5/12
Townsend – 1/2

FIRST SERVE PERCENTAGE  
Halep – 63 
Townsend – 66

PERCENTAGE OF POINTS WON ON FIRST/SECOND SERVE 
Halep – 75/58
Townsend – 47/42

TOTAL POINTS 
Halep – 66 
Townsend – 43