Kwanthai Sithmorseng will challenge WBA light-flyweight champion Kazuto Ioka in Japan today.
Kwanthai Sithmorseng, right, and Kazuto Ioka.
The 29-year-old former WBA minimumweight champion is considered the underdog against the unbeaten Japanese.
Kwanthai's manager Niwat Laosuwanwat said his boxer was more experienced and more skilful than the champion but was inferior to the Japanese on the mental side.
"If his mental side is strong enough, then he can become champion again," he said.
Kwanthai (43-1-1, 22KOs), now the Paba minimumweight champion, is ranked fifth in the light-flyweight division.
It will be his second shot at a world title after winning the WBA minimumweight crown by beating compatriot Pigmy Kokietgym in November 2010.
But his reign was short-lived when he lost to Indonesia's Muhammad Rachman in his first title defence.
The 24-year-old Ioka, who won all his first 12 fights (8KOs), claimed the WBA 108-pound belt in December with a sixth-round knock-out win over Jose Alfredo Rodriguez.
In May, he stopped Thailand's Wisanu Kokietgym in the ninth round to successfully defend the title for the first time.
He also took a fifth-round knockout win over champion Oleydong Sithsamerchai of Thailand to win the WBC minimumweight title in February 2011.