(CNN) -- Rafael Nadal took another big step towards a ninth French Open title Saturday while one of his chief rivals in his half of the draw Andy Murray hovered on the brink of elimination before play was halted in fading light.
Wimbledon champion Murray and Germany's Philipp Kohlschreiber were locked at 7-7 in the fifth and final set on Suzanne Lenglen.
The British seventh seed will be ruing several lapses of concentration, seeming to have the match in his grasp when a break up in the fourth set and again in the decider.
Each time Kohlschreiber, who won the Dusseldorf event last week, hit back and survived some nervous moments in the final game on his own service to keep the match alive.
The pair will come back Sunday with the winner to face either home favorite Richard Gasquet or Fernando Verdasco in the fourth round.
Verdasco led 12th seed Gasquet by two sets and it was 2-2 in the third set when their match was also halted in the gloom.
Earlier, top seed Nadal dispatched Leonardo Mayer in straight sets 6-2 7-5 6-2 and has yet to drop a set, while his Spanish compatriot David Ferrer also went through in fine style against Italy's Andreas Seppi.
Ferrer is a potential quarterfinal opponent for Nadal but first the four-time defending champion must get past fast-rising Serb Dusan Lajovic.
Match of the middle Saturday at Roland Garros may well have been Gael Monfils' five-set defeat of Italian 14th seed Fabio Fognini.
Ever popular Monfils prevailed 6-2 in the decider after dropping the fourth to love.
While the established order is, in the main, still on top in the men's draw, Simona Halep, a 22-year-old Romanian, is the highest surviving seed in the women's tournament.
The fourth-ranked Halep was impressive again in a 6-4 6-0 win over Spain's Maria-Teresa Torro-Flor, but standing in her way for a quarterfinal place is Sloane Stephens of the United States.
Stephens, 21, reached her sixth straight grand slam fourth round, the best record on the WTA Tour, with a 6-3 6-4 win over Russian Ekaterina Makarova.
Stephens, who many see as a natural successor to Serena Williams, says she is more motivated at the big four events rather than regular tournaments.
"I just peak at four tournaments a year. Every other tournament just gets me ready for these," she told the official French Open website.
Halep is determined to make amends for a defeat to Stephens the only time they have met.
"I played her in Australia a couple of seasons ago and she beat me very fast. Now I think I'm more prepared than I was then. I have confidence I can take revenge."
Former French Open champion Svetlana Kuznetsova will be a representative of the "old guard" in the last 16, with the 28-year-old, a 100-1 outsider at the start of the tournament, emerging as a real threat.
She battled to a 6-7 6-1 9-7 victory over Czech fifth seed Petra Kvitova, her 10th appearance in the last 16 at Roland Garros in 11 years.
She will next play Lucy Safarova, who continued the string of upsets with a 6-3 6-3 win over 2008 champion Ana Ivanovic.
Only one player from the top six of the rankings, Halep, is in the last 16, with seventh seed and 2012 champion Maria Sharapova favored by many to claim a second French Open title.
She will play Samantha Stosur of Australia in an eagerly-awaited fourth round clash Sunday.
Second seed Novak Djokovic and Roger Federer headline the action on Philippe Chatrier with intriguing match ups against Jo-Wilfried Tsonga and Ernests Gulbis respectively.