So, the rookie running back bounced up to his feet and sprinted several yards upfield even though the whistle had already been blown.
It was an act of determination prompted not only from a desire to make up for the eight practices and one preseason game that the third-round draft pick missed with a recurring hamstring injury, but also spurred by the motivation of being a new father.
Pierce's fiancée gave birth to a son named Bernard Jr. on Aug. 5.
"It's a great feeling, one of the greatest feelings in the world," Pierce said. "I've got to provide. It's not just about me. I've got mouths to feed."
Pierce returned to practice Saturday, his first full practice since aggravating a hamstring injury initially suffered in June during a rain-soaked minicamp practice.
The Ravens wanted to be cautious with the former Temple standout since this marked the second time he had hurt the same leg.
"We went really slow with him, plus his fiancée had the baby," Ravens coach John Harbaugh said. "They are doing well, and they had a couple of rough spots with it, so blessings to them.
"Everything turned out well. That gave him a little bit more time to get the hamstring healthy, really. It worked out timing-wise, and he seems like he’s fine.”
Signed to a four-year, $2.65 million contract that included a $555,000 signing bonus, Pierce is competing to be the primary backup to Pro Bowl running back Ray Rice.
Other than undrafted rookie Bobby Rainey, who scored a touchdown and gained 140 all-purpose yards against the Atlanta Falcons, none of the other backup candidates have distinguished themselves.
There's a prime opportunity to be the replacement for Ricky Williams, who abruptly retired after backing up Rice last season.
"I'm not worried about the time I missed," Pierce said. "I'm just glad to be back out there. I'mable to run and cut and do everything I need to do. I'm just working hard and getting back into the flow of things."
Pierce rushed for 3,570 career yards and 53 touchdowns in college, gaining 1,481 yards last season.
Pierce has practiced two days in a row without any setbacks, an encouraging sign.
"If I wasn't all the way back, they wouldn't let me out there," Pierce said. "It was sore from the first time, and it got worse than it already was. I wanted to make sure I was completely healthy before I went back out there.It's a long season, so you've got to take care of yourself."