Felix Alvarado may have withdrawn from his junior flyweight unification bout with Ken Shiro, but one of his recent rivals has stepped in to take his place.

Shiro will now defend his WBC junior flyweight title against Filipino contender Randy Petalcorin on the Dec. 23 card at the Yokohama Arena in Japan. The fight, which will be Shiro’s seventh defense, is part of the triple header that is headlined by Ryota Murata vs. Steven Butler, and includes Moruti Mthalane’s IBF flyweight title defense against Akira Yaegashi.

Petalcorin (31-3-1, 23 knockouts) of Davao City, Philippines has won two in a row against nondescript opposition over the past five months, since his seventh round technical knockout loss to Alvarado for the IBF junior flyweight belt he now holds. Jim Claude Manangquil, who promotes Petalcorin, says Shiro, who is more of a boxer, is a better style for him to face than Alvarado was.

“I like this better than the Alvarado fight,” said Manangquil. “[Shiro] is not that rough, or a pressure fighter like Alvarado.”

Manangquil says that Petalcorin had been in the Sanman Gym in General Santos City for a little over a week when they got the call to replace Alvarado, who has reportedly come down with a lung illness, and says they have to make the most of a five-week training camp.

“We can’t waste time,” said Manangquil.

Shiro (16-0, 9 KOs) of Kyoto, Japan is the no. 1 contender at 108 in the RING ratings, just underneath champion Hiroto Kyoguchi. Both Petalcorin and Shiro are 27 years old.