By Chris LaBate

Light heavyweight contender Yusaf Mack (29-3-2, 17 KOs) is very motivated for Saturday's fight with IBF champion Tavoris Cloud (22-0, 18 KOs). The Philadelphia boxer made a promise to his dying father, and he vows to make good when he faces Cloud in an HBO televised fight from St. Charles, Mo. The main event will feature a battle of junior welterweights, as Devon Alexander (21-1, 13 KOs) face Lucas Matthysse (28-1, 26 KOs).

"My dad passed away about 2 years ago," Mack told scribe Bernard Fernandez. "On his deathbed, he said he wanted me to be world champ, so I promised him that. And that's what I've got to do."

The two fighters have a common opponent, Glen Johnson. Mack was stopped in six rounds by Johnson in February of 2010, while Cloud won a twelve round unanimous decision over Johnson on August 7 of 2010. Mack admits to underestimating Johnson because of his age [he was 41 at the time of the fight], but promises a different outcome on Saturday.

"Going in, I thought Glen was [too] old," Mack said. "I took Glen for granted. I should have taken care of business. This fight will be different."