Running back Buck Allen made no excuses for his critical fumble that cost the Ravens dearly in Sunday's 34-14 loss to the Chiefs.

The rookie running back coughed up the football near the end of the first quarter, and the Chiefs returned it for a 73-yard touchdown. The play swayed the momentum of in the game, and Allen spent the rest of the afternoon watching from the sidelines.

"It can't happen," Allen said. "I take it upon myself, and it can't happen. I'm a pro and it's something that shouldn't happen."

The fumble was the second in as many weeks for Allen, and the Ravens' starting running back said he wasn't surprised by the coaching staff's decision to bench him the rest of the game.

"You play the best players, and at running back, the best players don't fumble," Head Coach John Harbaugh said. "Fumbling is what it is. You have to hold onto the football. He knows that."

The Ravens turned to Terrance West and undrafted rookie Terrence Magee to take the rest of the reps after Allen's turnover. Keeping Allen sidelined likely won't carry into next week's matchup with the Steelers, Harbaugh said.

"I have a lot of love and respect for Buck. In no way is Buck going to be banished, by any stretch," Harbaugh said. "He's done a lot for us. He has a great future for us. But you have to hold onto the football. That football belongs to everybody in the organization, every fan, everybody that cares about the Ravens. And it's a precious, precious commodity."

Allen's fumble came on the Ravens' second drive of the game, with the score tied at 7. The Ravens were marching into Kansas City territory and had the ball at the Chiefs' 30-yard line. Allen ran up the gut for 3 yards, but linebacker Derrick Johnson punched out the football and safety Tyvon Branch returned it for the score.

The Ravens trailed the rest of the game after that play.

"I just have to keep both hands on it and go down with the ball," Allen said. "I take full responsibility for it. That's all me, and [I have to] move on from it."

The significance of the fumble clearly weighed heavily on the rookie, and a handful of teammates came his way to offer support. 

"I just told him to keep his head up. I fumbled twice last season so I know the feeling," fullback Kyle Juszczyk said. "You know he's going to get another shot.  He obviously didn't get it today, but he's a talented guy. He's shown he's reliable before.  He'll take his punishment and he'll come back and I'm sure he'll do a great job."

Before last week's game against Seattle, Allen had gone all season without a fumble. He now has two fumbles in his 139 touches. 

The fourth-round pick has shown promise as a playmaker since Justin Forsett's season ended with a broken arm, and the Ravens have high hopes for what he can do in the offense.

They just need him to shake off the mistakes and protect the football in future weeks.

"This game is behind us. Move on, get ready for next week and make the best of it," Allen said. "I'm still going to have the same mentality – play hard, make plays when my number is called."