The 30-year-old Spaniard has won five titles this year and will make his fourth Grand Slam last-four appearance on Saturday.
"Of course, this season was the best of all my career," he is quoted as saying by Reuters. "I don't know why.
"I am playing with very confidence. I am older, you know, I don't have too much pressure."
Ferrer has yet to reach a Grand Slam final in his career.