It's in the bag

Dewie the Champ, Champion boxer came jogging into the room of the training facility passing his training instructor. The instructor looked at Dewie and spoke. "No need to worry, Dew. You will win the match. It's in the bag." The trainer left. Dewie walked to his favorite punching bag. Every time he pounded the sac of sand the sound was music to his ears. Remnants of sweat from his knuckles stained the outer bag. Bare fists were Dewie's motto usually except when it came to an actual brawl in the ring. He wanted to feel the aggressive pain that you could only receive bare fisted.
Today was different as Dewie jogged to the punching bag.
Dewie punched the bag..
Crunch, crunch...
"What the..? Crunch..?" Dewie questioned. The sound was terrible.
Dewie also heard a moan coming from the bag. He had thought it was all in his imagination. He Hit it again. Crunch, crunch… THAN! SMACK, SMACK! WET! It was very wet. Where yellow sweat stains had been on the punching bag, a formation of ruby blemished. The color spread outward like a whirling sea of whoa.
Dewie looked at his knuckles. Red droplets rained down from his appendages.
"What was in the bag?” Dewie asked out loud. All Dewie could think of was to use his pocket knife on the bag to rip it open. Like an infant child Dewie saw Charles, Chicago Champion as well as Dewie's opponent for tomorrow fall out onto the floor, naked, blood drenched, bruised and dead. He remembered his trainer’s words "No need to worry, Dew. You will win the match. It's in the bag."