"It's possible his ankle injury prevented a potential trade with teams," ESPN's Jeremy Fowler said on Thursday.
Fowler explained the Eagles were shopping Ertz prior to the Nov. 3 trade deadline, although the ankle injury undercut those efforts.
According to Spotrac, Ertz has a potential out on his contract in 2021.
Ian Rapoport of NFL Network reported on Sept. 3 that contract negotiations between Ertz and the Eagles "came to an abrupt halt" when the team seemed to low-ball him on an offer. The tight end told reporters the next week that the negotiations have been "frustrating at times" and "difficult" even though he said he wanted to remain with the team.
"I'm going to play this year like it's my last year," he added.
The Stanford product has been with the Eagles his entire career since they selected him with a second-round pick in the 2013 NFL draft. He is a three-time Pro Bowler who helped the team win a Super Bowl during the 2017 campaign, but he has just 178 receiving yards and one touchdown through six games this year.
That is a far cry from his typical production after he posted a career-best 1,163 receiving yards in 2018 and followed with 916 receiving yards and six touchdown catches last year.
Still, Ertz has dealt with health concerns and is set to turn 30 years old in November. The presence of the younger Dallas Goedert, 25, means the veteran may be expendable in Philadelphia's eyes, especially if it saves the organization from paying him a significant amount of money in a new contract.
Goedert tallied 58 catches for 607 yards and five touchdowns last year.