LOS ANGELES — Linebacker Alec Ogletree has agreed to a four-year contract extension with the Los Angeles Rams through the 2021 season.

Ian Rapoport of NFL.com tweets that the extension is worth $42 million with $30 million guarentee.

The Rams (3-2) announced the deal Thursday night with their top tackler and a key leader on their defence.

Ogletree is in his fifth season with the Rams, who drafted him in the first round out of Georgia. He took over a key role as their middle linebacker last season, and he has remained prominent during their switch to a 3-4 defence this season under new co-ordinator Wade Phillips.

Ogletree leads the Rams with 54 tackles in five games this season, including two sacks. He had 171 tackles by the team's count last season, the fifth-highest total in Rams history.