The Eagles have officially listed Howard as questionable for the team's Super Bowl rematch Sunday afternoon against the Patriots at the Linc.
Howard suffered a stinger in the Eagles' win on Nov. 3 against the Bears, his former team.
That means Jay Ajayi, who the Eagles re-signed on Friday, should be active for the first time in over a year and will likely have a role.
Howard, in his first year with the Eagles, has 525 rushing yards, a 4.4 average and seven touchdowns, including one receiving.
Since Week 4, Howard has been the 13th-leading rusher in the NFL, averaging 71 yards per game and 4.5 yards per carry.
Howard was limited in practice during the week and head coach Doug Pederson said Friday he had not been cleared for contact, which left him with a remote chance to be active on Sunday.
Howard has never missed a game because of injury. He didn't play in the Bears' 2016 opener against the Texans - opening day of his rookie year - but he did dress for the game and was active, he just didn't get onto the field.
Since then, he's played in 57 of a possible 57 games.
Howard has the second-most rushing yards in the NFL since 2016 behind only Ezekiel Elliott of the Cowboys.
The Eagles are already down two running backs. Super Bowl hero Corey Clement is on Injured Reserve with a shoulder injury and Darren Sproles joined him on Injured Reserve this week with a season-ending quad injury.
The Eagles will go into Sunday with Miles Sanders, Ajayi and Boston Scott. They also have a rookie, De'Angelo Henderson, on the practice squad.
Sanders, after a slow start, is averaging 4.4 yards per carry on 76 for 336 and has 22 catches for 305 yards.
Ajayi, acquired by the Eagles from the Dolphins midway through the 2017 Super Bowl season, hasn't played since injuring his knee in a game against the Vikings on Oct. 7 of last year.
Ajayi has battled knee injuries most of his career but his 4.5 career average is fifth best in the NFL since 2015 among running backs with at least 500 carries.
Scott has 16 carries for 68 yards, a 4.3 average in limited duty.
The Eagles have averaged 141 rushing yards in their last six games. The Patriots are allowing an NFL-worst 5.6 yards per carry over their last six games.
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