Coria posted an emotional 6-3, 6-7 (3-7), 6-0 victory over Gaston Gaudio after Calleri surprised eighth seed David Nalbandian, last year's Wimbledon finalist, 6-4, 6-1.
It was the first time in the 13-year history of the Tennis Masters Series that all four players in the semifinals came from the same country.
Coria received treatment three times for calf and thigh injuries in a grueling two-hour, 30-minute encounter.
"The trainer and the physio are like geniuses and without their help on court I would not have been able to finish the match," he said.
Even though Coria's ground strokes could make him a French Open title contender, the 21-year-old could barely hobble to the net to shake hands at the end, and his fitness for the final will not be known until he appears.
"I think I will be OK tomorrow," Coria said. "I have a lot of hours in which to prepare for the final, and I will eat very well tonight. It should be a great final because we are both playing the best tennis of our careers."
After the match Gaudio was seen to put his hand on Coria's shoulder and shake him, but both players denied allegations that there had been bad blood between them.
"There was no disagreement," Coria said. "Maybe he thought I was going to stop the match because of cramps and he thought he had the match. At the end, he was upset because he lost."
There were moments of high drama in the second set tiebreaker when Coria called a shot out during the course of the rally, only for the umpire to stop it and penalize him for interceding, awarding the point to Gaudio.
That put Gaudio up, 2-0, in the tiebreaker, which he eventually won to level the match at one set apiece. But his mood changed only a few minutes later.
After Coria took a 3-0 lead in the final set, Gaudio hurled down his racket -- damaging it -- and received a warning from the umpire.
When Coria won the next game quickly, he tapped provocatively on his heart, as if to say this was what Gaudio lacked.
Coria advanced to his third final of the year. He lost to Carlos Moya in the Buenos Aires final earlier this season and appeared in his first Tennis Masters Series final in Monte Carlo last month. His only career title came at Vina del Mar two years ago.
Nalbandian and Calleri both found great angles from the baseline and were happy to move into the net when the need arose, which made for a lively, unpredictable match.
Unfortunately for Nalbandian, his game also was unpredictable, and each time he worked his way to a position of advantage he would over-hit or allow himself to be outplayed. He was clearly disappointed with the outcome, only his second loss to Calleri in five meetings.
"Sometimes you wake up good and sometimes you wake up bad," said Nalbandian, who failed to convert eight break points.