BANGKOK, Thailand -- Rising tennis star Paradorn Srichaphan is being advised to dump his father as coach if he wants to break into the world's top 10.

Paradorn won the Stockholm Open on Sunday, his second ATP title this year, and moved to No. 21. He began the year at 120. He's won 25 of his last 31 matches, and beaten No. 1 Lleyton Hewitt and No. 2 Andre Agassi in the last six months.

Paradorn's father, Chanachai Srichaphan, has been his coach since he was 6. Yet, Thai critics believe Chanachai should step down.

"If (Chanachai) was not great, Paradorn would not have come this far," said Sathien Mongtrongtham, vice president of the Lawn Tennis Association of Thailand. But, "what he needs is time-to-time consultations with foreign coaches to improve some techniques."

Pitsanu Nilklad, a television sports commentator, said, "It is time for him to be supervised and looked after by a world-class coach.

"You can fire your coach but you can't fire your father. It is up to Chanachai whether he is willing to give up the job."

Chanachai gave up a bank job to dedicate most of his adult life to coaching Paradorn and his two older brothers, who were top national players. A strict taskmaster, he always had a soft spot for the youngest member of the family.

Chancahai would cuff the others if they made mistakes but never raised his hand against Paradorn, his brother Narathorn, recalled.

Paradorn said last month he had no intention of firing his father.

"Our combination has worked well so far. He is a great coach, a great father, a great friend," said Paradorn, who wears a red T-shirt on court for luck.