WBC lightweight king David Diaz vowed to beat Filipino boxing champion Manny Pacquiao when they meet face to face on June 28 at his own game: power for power.

"I will beat Manny at his own game—power for power," Diaz was quoted as saying in a report posted on Sportsnews.ph.

Pacquiao and Diaz met face-to-face during their Chicago stop to promote their face-off dubbed "Lethal Combination".

Diaz’s camp said they will outdo Pacquiao when the Filipino bomber climbs the ring together with their ward at the Mandalay Bay Events Center in Las Vegas, Nevada.

"Manny is a tremendous fighter with fast hands. What we're training for is if he hits us with a three-punch combination, we're going to hit him back with a four-punch combination. If he hits us hard, we're going to hit him harder," said Diaz’ manager Jim Strickland.

The reigning WBC lightweight champion has a 34-1-1 record with 14 knockouts.

For his part, Pacquiao said he will dedicate the bout, his toughest fight to date, to his countrymen.

"This will be my hardest-fought battle—it has been three years since I have changed weight divisions and I will be doing it against the lightweight world champion," Pacquiao said.

"I am fighting for history—five world titles in five different weight classes—and I am fighting for my people of the Philippines," he added.

The 29-year-old Pacquiao, who sports a record of 46-3-2 with 35 knockouts, recently won the WBC super featherweight crown via split decision over bitter Mexican rival Juan Manuel Marquez last March 15.

The win made Pacquiao the first Asian to score three championships belts in three different divisions. Aside from winning the super featherweight belt, he also held titles in the flyweight and super bantamweight divisions.

On the other hand, the 31-year-old Diaz snatched the WBC interim lightweight crown against the favored Mexican Jose Armando Sta. Cruz via 10th round TKO August of 2006. Dennis Principe, Sportsnews.ph