OWINGS MILLS, Md. -- Defensive tackle Michael Pierce accepted responsibility for being pulled from practice during last week's Baltimore Ravens mandatory minicamp, blaming it on an error in his training regimen.

"Throughout the offseason, I tend to lift more than run," Pierce told WNSP-FM radio in Alabama on Friday. "Being a noseguard, I want to be strong or whatnot. I, honestly, just mismanaged my running a little bit."

Pierce reported to the Ravens last week significantly heavier than his listed playing weight of 340 pounds. A restricted free agent, Pierce didn't attend the team's offseason conditioning program and sat out all of the voluntary practices in the spring.

On Tuesday, Pierce left the field following the stretching portion of practice after speaking to coach John Harbaugh, who later told reporters that the fourth-year lineman wasn't ready to practice "from a safety standpoint and for his own health."

"Out of respect for Coach Harbaugh, he's been nothing but a fair guy, he just wanted me to get in with the strength and conditioning staff and do more running before camp comes," Pierce said.

Baltimore defensive coordinator Don "Wink" Martindale expressed disappointment that Pierce wasn't in shape to practice but cautioned anyone against piling on him.

"Let's don't forget what a great football player he is," Martindale said last week. "He'll get back there. I can't tell you when, but he'll get back there."

Pierce, 26, was ranked as the fifth-best interior defensive lineman by Pro Football Focus last season. Considered one of the better run defenders in the NFL, Pierce received a second-round tender this offseason and will earn $3.095 million.

He signed as an undrafted rookie out of Samford in 2016, and his weight had previously never been a major issue. This is an important year for Pierce, who can become an unrestricted free agent after the season. But his season didn't start smoothly.

"At the end of the day, you expect a team leader to come back in better shape than I did," Pierce said. "That's a mistake on my behalf I have to correct. I don't want to get into much more than that."

The Ravens report to training camp in about 5½ weeks.