After 19 years of racing at NASCAR's highest level and 26 victories, Dale Earnhardt Jr. has decided to retire at the end of the 2017 Cup Series season.

Earnhardt, who has suffered a series of head-related injuries since 2012, missed the second half of this past season after several hard accidents and a concussion diagnosis. Because of the after effects of his latest head injury, Earnhardt waited until the offseason to finalize contract details with Hendrick Motorsports.

Since his return, Earnhardt only has one top 10 finish in eight starts this season. He crashed out of Monday's race at Bristol Motor Speedway -- his third DNF in 2017 -- after an issue with his car caused him to hit the wall entering Turn 2.

Recent events in his personal life may have also factored into his decision. Earnhardt, 42, was married in the offseason, and shortly after his announcement,
his wife, Amy, released a statement on Twitter.

[tweet url="https://twitter.com/AmyEarnhardt/status/856865602962677760" hide_media="0" hide_thread="1"]
The timing could not be worse for NASCAR, which is struggling to build a younger and more engaged fan base. Earnhardt was voted NASCAR's most popular driver for a record 14 straight years.

"Dale Jr. has had a huge impact on our sport -- and you can see that every week with his legion of fans and Junior Nation," former Hendrick Motorsports teammate Jeff Gordon said in a press release. "He has a tremendous sense of the history of NASCAR, and, while he shares his father's name, Dale has made a name for himself with his accomplishments in racing. While we will miss Dale on the track next year, he loves this sport, those working in the industry, and the fans too much to ever be too far away."

A press conference has been scheduled for 3 PM Eastern for Earnhardt to formally announce his decision.

Concussion & Injury Timeline

2002
Suffered first concussion of his career at Auto Club Speedway in April; did not admit it until mid-September. Between these to dates, he won both Talladega races

2012
August: A hard wreck in tire test at Kansas. Didn't go to the doctor but had symptoms until Talladega SuperSpeedway.
October: Involved in a 25-car last lap crash.
October: Missed two Chase races after Talladega.

2016
April: Announced that he will donate his brain to research to study the effects of concussions.
June: Crashed with Chris Buescher at Michigan International Speedway.
July: Involved in a mutli-car wreck at Daytona International Speedway.