Ken Rosenthal of The Athletic reported the update Tuesday and noted an official announcement from the club is expected Friday.
Yelich has two guaranteed years and a club option for 2022 left on a seven-year, $49.6 million contract he signed with the Miami Marlins in March 2015. It's unclear whether the new deal will replace the remainder of that pact or be added on the end, per Rosenthal.
The 28-year-old California native has been one of MLB's top players since Miami traded him to Milwaukee in January 2018.
He was named the National League MVP in 2018 after posting a 1.000 OPS with 36 home runs and 22 stolen bases in 147 games. His numbers were more impressive in 2019 as he recorded a 1.110 OPS with 44 homers and 30 steals across just 130 appearances.
His WAR (15.4) ranks fourth among MLB hitters since the start of 2018 behind only the Los Angeles Angels' Mike Trout (18.4), Los Angeles Dodgers' Mookie Betts (17.0) and Houston Astros' Alex Bregman (16.0), per FanGraphs.
Yelich said in February there will be "no lack of motivation" heading into the 2020 season after a knee injury cut short his 2019 campaign in September.
"It's hard to stay disciplined every day," he told reporters. "You really have to bear down and focus, but I feel like if you do that, you make good decisions, and walks help the team too. That's just how I've done it; it's what I did last season, especially toward the end there, and it's what I'm going to work on again this year."
Yelich and the Brewers will open the regular season March 26 against the Chicago Cubs.