Ecuador's sixth seed Nicolas Lapentti saved five match points before defeating Spanish teenager Rafael Nadal 3-6 6-3 7-6 to reach the Swedish Open semi-finals on Friday.
Top seed and defending champion Carlos Moya also reached the last four, the Spaniard comfortably defeating Swedish doubles specialist Jonas Bjorkman 6-4 6-3.
In a marathon match lasting almost three hours, Lapentti needed to play his best tennis to oust Nadal, who had dominated the opening set.
Lapentti mixed his serve and volley game with some clever drop shots to get back into the match. The final set was a tense affair that could have swung either way, before the Ecuadorian won the tiebreak 8-6.
He now takes on either Spaniard Tommy Robredo or Italian Filippo Volandri, who play later on Friday.
Earlier, Argentine Mariano Zabaleta ousted Russian fourth seed Mikhail Youzhny 4-6 7-5 6-1 to reach the last four.
The fifth seed recovered from 4-2 down in the second set as Youzhny crumbled under pressure.