Top seed Juan Carlos Ferrero overpowered Brazil's Flavio Saretta 7-6, 6-2 to reach the final of his hometown tournament on Saturday.
Ferrero edged the first set 7-3 on the tie-break and clinched victory by reeling off four games from 2-2 in the second.
The Spaniard's reward will be a final against Christophe Rochus, after the Belgian continued his unexpected run with a 6-3, 6-2 success against Fernando Vicente.
"When it really mattered I played good tennis and that took me into the final," Ferrero told reporters after the match.
Ferrero beat Rochus in straight sets when they met in the Davis Cup this year and the world number three will be confident of another win over the Belgian, who came to Valencia without a win since the Australian Open in January.
"I did beat Rochus easily last time," Ferrero noted. "I hope the crowd continue to give me plenty of support against him in the final."
If Rochus, who has never won on the ATP tour, can find the same fluent form he displayed against Vicente, Ferrero may not have things all his own way in the final.
Rochus broke in game six for a 4-2 lead on a slow clay surface and went on to take the first set in just 30 minutes.
A nervous looking Vicente never managed to put Rochus under pressure on his own serve and the Belgian broke again at the start of the second.
Rochus improved that to 2-0 with a love service game and broke again for 5-2 before serving out for victory.
"Rochus dominated from start to finish," Vicente recognised. "He's very talented and if he has one of those weeks when everything is going right he can beat anyone."
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