Pierce will step in for Ray Rice, who is serving a two-game suspension for domestic violence.
''I'm as excited as I can be, but at the end of the day I can't really overthink it,'' Pierce said after Wednesday's practice. ''I just have to make sure I stay mentally locked in and focused because, you know, this could possibly be my only shot. If you can't handle the load, somebody else will.''
Pierce already has shown he can handle at least some of the load. He rushed for 532 yards in the regular season as a rookie two years ago, then ran for 202 more yards in four playoff games as the Ravens won the Super Bowl.
He also averaged 4.9 yards per carry in the regular season in 2012. His numbers slipped some last year as Pierce battled injuries (knee, shoulder) while working behind an ineffective offensive line. He finished with 436 yards and only 2.9 yards per carry.
Pierce then underwent shoulder surgery in the offseason and suffered a minor concussion in the third exhibition game versus Washington. He said he's fine now and ready to go in his second career start.
''I guess it's a good feeling,'' Pierce said. ''But we always have to prepare to be starters. So when you're needed, you've got to be ready to go at all times.''
Ravens coach John Harbaugh said he's confident Pierce will be do the job while Rice sits out. The Ravens picked Pierce in the third round of the 2012 draft from Temple, and Harbaugh said there's a reason he was selected that high.
''Bernard's a good player,'' Harbaugh said. ''He's got talent. He's tough. He works really hard. We've all seen him carry the ball at his best, and we just want to see him be his best. He's done a real good job.''
Pierce ran for 89 yards on 21 carries in the preseason and scored a touchdown.
Injuries slowed Pierce last year, but when he's right, he's effective.
''You've seen Bernard for a couple of years now. He's a good running back, especially when he's healthy and feeling good,'' quarterback Joe Flacco said. ''I think he's ready to go.''
The Bengals know that Pierce can cause problems as the focal point of new offensive coordinator Gary Kubiak's scheme.
''Bernard is a very good downhill runner,'' Cincinnati coach Marvin Lewis said. ''He's a strong, strong runner; he's a good screen runner. He does a lot of good things.''
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