The seventh-seeded Baghdatis, who won the Zagreb Open on Feb. 4, faces Gilles Simon of France in Sunday's final. Simon beat Robin Soderling of Sweden 6-2, 7-6 (2) in the other semifinal match.
Baghdatis, the 2006 Australian Open runner-up, said he was relaxed going into the final.
"There are things more serious than losing a tennis match," Baghdatis said. "I'm a cool guy and I'm happy in life. If I don't win, it won't be a drama, I will keep smiling."
After losing the opening set, Baghdatis regained his composure in the second set and used a series of drop shots to upset Nieminen's rhythm.
"At the end of the first set, I felt better, that I was getting my legs back," Baghdatis said.
Using his powerful forehand, Baghdatis quickly took a 3-0 lead in the deciding set, winning seven straight points in the process.
Baghdatis made it 4-1 with a perfect drop which Nieminen barely returned at the net, only for the Cypriot to whip a passing shot by him.
In the following game, Nieminen smashed his racket into the ground in frustration. Baghdatis clinched the match on serve when Nieminen hit a long forehand.
Simon broke Soderling three times in the first set and frustrated him during long rallies. In the second set tiebreaker, Simon's ace gave him a 3-0 lead. Soderling then lost his final two serves.