Simona Halep continued her swift progress through the draw to ease into the fourth round at Roland Garros.

The world number four is the highest seed left and the second favourite for the title behind Maria Sharapova despite only having reached one grand slam quarter-final.

Halep, who beat Britain's Heather Watson in round two, has not come close to losing a set so far and she chalked up a second love set of the week in beating Spain's Maria-Teresa Torro-Flor 6-3 6-0.

The 22-year-old should face her first real test in the next round against 15th seed Sloane Stephens, who is once again showing her best form in the grand slams.

Stephens is through to the second week at a sixth consecutive grand slam after defeating big-hitting Russian Ekaterina Makarova 6-3 6-4.

Stephens and Halep have met three times before, with the American having won the last two.

Halep, who is reading Harry Potter to help improve her English, did not expect to be the highest seed left at this stage of the tournament.

She said: "The first three seeds, they lost. That's a surprise for everyone.

"It's not easy to be the first seeded now in the tournament. But I try just to keep out from me the pressure and just to play every match.

"I played against (Stephens) in Australia a few years ago and she beat me very fast. Now I think I'm more prepared than that moment.

"I feel really great now, because I won in two sets, the third match here where I played really good tennis. It's not a surprise, because I'm more confident now in myself, and I'm feeling the ball really good."