"Maybe the last three matches is the best tennis (of my career)," Ferrer, 25, said.

"I'm playing really very well on hard courts and it's unbelievable. If you had told me before that I would get to a semi-final on hard courts, I would not have believed you. I believe in clay, maybe, but not in hard court.

"This tournament is a dream."

Ferrer was match point down in the third round to fellow Argentine David Nalbandian but fought back to win and then pulled off a stunning defeat of second seed Rafael Nadal in the fourth round.

Chela had won both their two previous meetings but Ferrer served superbly, ripping through the first two sets, though he did need seven set points to win the second.

The Argentine, in his second grand slam quarter-final, cut down his unforced errors in the third set and gave himself a glimmer of hope when he broke for 2-0.

But Ferrer broke back immediately and then again in the 11th game before serving out to set up a clash with third seed Novak Djokovic of Serbia or Spanish 17th seed Carlos Moya .

"That (2-0) was my only real chance, when I was ahead in the scoreboard but he broke me back right away," Chela said.

"He returned very well in that game, so that was gone very quickly."

The 28-year-old Chela was appearing in his first U.S. Open quarter-final and despite the defeat, said he was pleased with his efforts.

"It's maybe a little bit difficult to think about it now because I've just lost, but it's been a good tournament."

Ferrer has lost six of his eight matches with Moya, but leads his compatriot 2-1 on hard courts, while he has a 2-1 record against Djokovic, though he lost their only hard-court meeting.