Joe Mixon and the Bengals have agreed to a four-year, $48 million extension that will keep the star running back under contract with Cincinnati for five more seasons, according to ESPN sources and multiple reports.

The language of the deal was still being finalized Tuesday afternoon, a source told ESPN's Adam Schefter. NFL Network first reported the financial terms of the extension.

Mixon tweeted a picture of himself with members of the Bengals front office Tuesday before he joined the rest of the team for practice.

pic.twitter.com/Mckx5gsEKo

— ⚡️Primetime!!!⚡️ (@Joe_MainMixon) September 1, 2020

Mixon, 24, had been absent from practice recently as he suffered from migraines, according to Bengals coach Zac Taylor. Mixon declined to speak to the media during training camp, which ended Sunday.

Mixon, a second-round pick in the 2017 draft, was set to make $1.2 million this season in the final year of his rookie deal. The former Oklahoma star told ESPN at the end of last season that he wants to be a "Bengal for life," amid early speculation about his contract situation.

Mixon rushed for 1,136 yards and five touchdowns last season, his second straight season with over 1,000 rushing yards. He is one of four running backs in the NFL with at least 1,400 yards from scrimmage in each of the past two seasons, along with Carolina's Christian McCaffrey, the Giants' Saquon Barkley and Dallas' Ezekiel Elliott.

Mixon is fifth in the NFL in yards after contact since his rookie season in 2017, and has the league's seventh-most rushing yards since the start of the 2018 season.

Last week, Taylor said Mixon's absence was not related to his contract situation and that he was day-to-day with his migraines. Mixon and Taylor shared an embrace before Sunday's scrimmage, where Mixon did rehab work on the sideline after being absent from practice earlier in the week.

During Tuesday's practice, reporters spotted Mixon and team president Mike Brown engaged in a conversation. Brown has not held a news conference since before the 2019 season.

Mixon joins wide receiver Tyler Boyd, defensive tackle D.J. Reader and the rest of the 2020 draft class -- including rookie quarterback Joe Burrow -- as Bengals who are currently under contract through the 2023 season.