Updated

Stewart-Haas Racing has scheduled a news conference for 1 p.m. ET on Wednesday at the team's Kannapolis, N.C., headquarters, at which time driver and team co-owner Tony Stewart is expected to announce that 2016 will his last season behind the wheel, multiple sources with knowledge of the situation told FOXSports.com on Sunday night.

Gene Haas, Stewart's partner, will attend the news conference, the team confirmed.

Motorsports.com first reported Sunday night that Stewart would retire and sources confirmed the report to FOXSports.com. Stewart will be replaced in 2017 by Clint Bowyer, who will be a free agent this coming offseason after Michael Waltrip Racing closes at the end of the year.

Stewart, a three-time NASCAR Sprint Cup Series champion and one of auto racing's most versatile drivers, has struggled over the last two seasons after suffering a debilitating double compound fracture of his right leg in a sprint car accident in Iowa in August 2013.

In August of last year, Stewart was racing in a sprint car event in Upstate New York, when his car struck and killed 20-year-old Kevin Ward, who had crashed, climbed out of his car and ran towards Stewart's car. Stewart was exonerated of criminal wrongdoing, but Ward's parents filed a wrongful death civil suit that is still pending.

In an exclusive interview with FOXSports.com two weeks ago at Richmond International Raceway, Stewart declined to speculate about his future, saying he wasn't ready to discuss his plans. But now, he's prepared to make the change.

As a driver, Stewart has an impressive resume: Three Sprint Cup championships, 48 race victories and 182 top-five finishes in 582 career starts in NASCAR's highest level. Stewart also holds championships in the Verizon IndyCar Series, the now-defunct IROC Series and USAC, where in the same season in 1995 won the sprint car, midget and Silver Crown series championships.

Not much has worked for him this season, as Stewart is 25th in the points standings and failed to qualify for the Chase for the Sprint Cup championship for the third consecutive year. Stewart, who moved from IndyCar to NASCAR and got his break in 1999 with Joe Gibbs Racing, finished 11th at New Hampshire on Sunday and has not won a Cup race since June 2, 2013, at Dover.

Stewart is the second star in two years to call it quits. Four-time champion Jeff Gordon will retire at the end of this season.

-- The Associated Press contributed to this report