Dale Earnhardt Jr. is retiring from NASCAR at the end of 2017.

Hendrick Motorsports announced Junior’s decision Tuesday morning and said the driver would have a press conference Tuesday afternoon to explain the reasoning behind the decision.

Junior, 43, missed the second half of the 2016 season after suffering a midseason concussion and said he was going to wait a few races into the 2017 season to begin talks on a contract extension with Hendrick Motorsports.

His current contract expires at the end of 2017, and the announcement was the answer to why Junior tweeted Tuesday morning that he was up so early.

His retirement means NASCAR’s three biggest stars will have retired in consecutive seasons. Four-time champion Jeff Gordon, who helped sub for Earnhardt last season, retired at the end of the 2015 season, while three-time champ Tony Stewart hung up his firesuit at the end of 2016.

And while the retirements of Stewart and Gordon – along with the sudden departure of Carl Edwards – were NASCAR-rattling events, Junior’s has the potential to be even more so. Because of his popularity among fans that started out as fans of his father, he’s the last driver left who so clearly bridges old NASCAR and new NASCAR. The 14-time most popular driver award winner is so popular that Nationwide, which once sponsored NASCAR’s No. 2 series, moved to sponsor him after not renewing the series title sponsorship for what’s now the Xfinity Series.

“While Nationwide and the rest of Junior Nation will miss seeing him on the track, we fully support Dale Earnhardt Jr.’s decision to step away from racing in NASCAR,” a Nationwide statement said. “Dale Jr. has been a tremendous partner and friend to Nationwide. We look forward to continuing our relationship with him after the conclusion of what’s sure to be a memorable 2017 season.”

Junior finished 38th in Monday’s race at Bristol after an apparent oil line issue caused his car to hit the wall. He has 26 career Cup wins in 603 starts and finished third in the points standings in 2003. He was 12th in 2015, his last full season in the Cup Series. He’s currently 24th in the points standings and has a chance to make NASCAR’s playoffs for a final time if he wins a race or gets high enough in the points standings.

Hendrick Motorsports said future plans for the No. 88 team would be announced at a later date.

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Nick Bromberg is the editor of Dr. Saturday and From the Marbles on Yahoo Sports. Have a tip? Email him at nickbromberg@yahoo.com or follow him on Twitter!

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