BEREA, Ohio -- The Cleveland Browns and All-Pro offensive guard Wyatt Teller have agreed to a four-year, $56.8 million extension, a source told ESPN's Dan Graziano.

ESPN's Kimberley Martin reports the deal includes $28 million in guarantees.

Teller has been a stalwart at right guard for the Browns the past two seasons.

Acquired from Buffalo before the 2019 season, Teller took over as a starter at right guard midway through the year. Last season, Pro Football Focus gave Teller its highest grade among offensive linemen. Thanks in part to Teller's emergence, Cleveland ranked third in the league in 2020 in rushing yards.

In two years as Cleveland's general manager, Andrew Berry has invested heavily in the Browns' offensive line. Last offseason, he signed All-Pro right tackle Jack Conklin to a three-year deal worth $42 million, including $30 million guaranteed. Berry also spent the 10th overall pick in the 2020 draft on Alabama's Jedrick Wills Jr., who immediately won the starting job at left tackle.

After struggling throughout the 2019 season, the Browns' offensive line has been among the league's most dominant units. Teller has been a major reason for the turnaround.

This season, the Browns rank No. 1 in pass block win rate and No. 9 in run block win rate.