Scherff, 28, is due $15 million in 2020. The two sides had until the July 15 deadline for all franchised players to ink a long-term deal.
Scherff had previously indicated talks were going "well" before they apparently lost momentum over the last few months.
"It's gone well," Scherff said in April of negotiations. "Just pretty much sat down and talked to my agent—that's what he's there for—and I want to sign a long-term deal with them, too. I love it there, and I've always said I wanted to be [with this organization] for the rest of my career. So, hopefully we can work towards that."
Scherff has been limited by injuries each of the last two seasons, missing eight games in 2018 and five in 2019.
When he has been on the field, Scherff has remained a reliable run and pass-blocker. Pro Football Focus gave him a solid 75.0 grade last season, but he did commit nine penalties—tied for second-most among guards.
Both sides may have some interest in Scherff proving he can stay healthy—the team from a commitment standpoint, Scherff from a financial—before they wind up committing past 2020.