In all, the Bills released 21 players Friday as they trimmed their roster to the 53-man limit.
Lawson, 32, was expected to start opposite Jerry Hughes in the Bills' 3-4 defense until first-round pick Shaq Lawson (shoulder surgery) returns from the physically unable to perform list. The earliest Lawson is eligible to return is Week 7.
Without Manny Lawson, the Bills will start veteran Lorenzo Alexander at outside linebacker.
"Lorenzo Alexander has earned the right to be a starter on this team. He won the job. That's why he'll start," Bills coach Rex Ryan said. "As far as specifics [on Lawson], I'd rather not get into specifics."
Gronkowski, an undrafted rookie from Kansas State, is the youngest of five Gronkowski brothers who are natives of the Buffalo suburb of Williamsville. Rob Gronkowski is a star tight end for the New England Patriots, and Chris and Dan Gronkowski are both former NFL players.
"I think with Glenn, I thought we did a lot of things with him. We put him in at some tight end spots. We put him in a the 'U' tight end. We put him in at fullback. And he gives some special teams depth," Ryan said. "So I think that was what's been impressive with this young man. But I wanted to see him be more physical. And I think he showed that a little bit [in the final preseason game]."
Glenn Gronkowski, whose nickname is Goose, was congratulated Friday on Instagram by his brother Gordie, a former draft selection of the Los Angeles Angels:
I couldn't be more proud of this kid @glenn_gronkowski Just another step forward & still a long way to go but he stuck with his beliefs to make his dream come true! Avoided the outside noises and worked his ass off day in and out to be the best teammate, football player & family guy he could be. Remember the train doesn't stop here!! A Big Big congrats from your oldest bro!!! #bropowers #buffalobills #yourstory #gronkfitness #believe #jb #preperation
Manny Lawson was the only projected starter who played the entire first half of Thursday's preseason finale loss to the Detroit Lions. Ryan said this week he wanted to give the linebacker playing time because he missed the first two preseason games as he recovered from a partially torn pectoral muscle.
Lawson remains under investigation by the NFL for a potential violation of the league's personal conduct policy. A league representative said Thursday there was "no update" in the case.
Although it remains unclear what incident the league is investigating Lawson, the veteran linebacker has acknowledged he was charged in Scottsdale, Arizona, with misdemeanor disorderly conduct/domestic violence in February 2014. Lawson denied there was any "physical violence" in the incident; the charges were later dropped upon the completion of a diversion program.
The Bills will save $2.35 million on their salary cap by releasing Lawson, who signed a four-year deal with Buffalo as a free agent before the 2013 season and has started 29 games over the past three seasons for the Bills in several roles under changing defensive coordinators.
The Bills will save $1.55 million against their salary cap by releasing Felton.
Felton acknowledged his release in a tweet Friday.
Thanks to everybody in and around the bills organization!! I enjoyed playing for the #BillsMafia far from finished ;)— jerome felton (@jfelton45) September 2, 2016
Lawson, originally a first-round pick of the 49ers in 2006, played five seasons in San Francisco and two seasons for the Cincinnati Bengals before joining the Bills.