Russia's Nikolay Davydenko overcame Argentine baseliner Guillermo Canas 7-5, 6-4, 6-4 on Tuesday to set up a semi-final showdown with world number one Roger Federer at the French Open.
World number four Davydenko, 26, showed more composure when it mattered to reach the last four at Roland Garros for the second time in three years.
The 29-year-old Canas, who returned to action last September after a 15-month doping ban, was bidding to make the semi-finals of a Grand Slam tournament for the first time. He has now fallen in the quarter-finals atthe French Open thrice.
Davydenko looked in control throughout a tight contest until converting the first match-point with a superb forehand winner after just three hours of play.
Federer's 36-set record winning streak in Grand Slam tournaments was snapped by Robredo but that did not stop the Swiss from sweeping into the semi-finals with a 7-5, 1-6, 6-1, 6-2 victory.
The world number one and Australian Open champion had not dropped a set at a major since losing the second in his four-set triumph over Andy Roddick in the US Open final last September.
Spanish ninth seed Robredo took the second set with a forehand crosscourt winner but it was not long before Federer was once again meting out punishment
The Swiss won the next five games in a row and after steaming towards victory, he sealed his passage to the last four with an exquisite backhand volley.