(PHOTO AND STORY: NASCAR.COM)
Dale Earnhardt Jr. will retire following the 2017 NASCAR season, Hendrick Motorsports announced Tuesday in a press release.
The 14-time Most Popular Driver has won 26 times in 603 starts over a career that began at age 24 in 1999. Among his accomplishments are two Daytona 500 crowns (2004, 2014) and two championships (1998, 1999) in what is now called the NASCAR XFINITY Series.
Earnhardt, 42, returned to competition in the No. 88 Chevrolet this year after a concussion sidelined him from NASCAR's top series for half of the 2016 season. Through his rehabilitation process, Earnhardt has become a vocal advocate for research of sports-related brain injuries.
Earnhardt's best finish in eight starts this season was fifth place at Texas Motor Speedway on April 9. He currently is ranked 24th in the Monster Energy NASCAR Cup Series standings.
Hendrick Motorsports said in a news release that it would announce its 2018 plans for the No. 88 team at a later date.
Earnhardt began his premier-series career on May 30, 1999 at Charlotte Motor Speedway with a 16th-place finish in the Coca-Cola 600. That step in his NASCAR career came after years of driving Late Models at the weekly and touring level before making his mark in the XFINITY tour.
Earnhardt followed the steps of his famous father, initially driving cars owned by NASCAR Hall of Famer and icon Dale Earnhardt. His earliest entries in the premier series carried No. 8, the number favored by his grandfather, Ralph Earnhardt.
The early part of Earnhardt's career was met with tragedy, with the death of his father in a last-lap crash in the 2001 Daytona 500. Earnhardt Jr. won in the series' return trip to Daytona International Speedway that summer, going 1-2 with teammate Michael Waltrip in an emotional victory for Dale Earnhardt Inc.
Earnhardt's most prolific year with DEI was a six-win season in 2004 that included his first Daytona 500 victory. By then, he had exhibited a mastery on the sport's biggest and fastest ovals, winning six times at Talladega Superspeedway, including a four-race win streak that stretched from 2001-03.RELATED: Go deeper in Dale Jr.'s career stats
After an acrimonious departure from his father's race team -- which continued under the leadership of his stepmother, Teresa Earnhardt -- Earnhardt's free-agency period in 2007 ended with his choice of Hendrick Motorsports. That move fulfilled a half-joking "lifetime contract" he'd jotted down on a napkin and issued to team owner Rick Hendrick as a teenager in 1991.
Earnhardt is now in his 10th season driving for team owner Rick Hendrick, a span that has ebbed and flowed with both triumph and setbacks. After winning at Michigan International Speedway in his first year with the team, he went four seasons before winning again -- also at Michigan.
Earnhardt caught stride again in 2014 and '15, combining for seven wins in that two-year stretch. That included his second Daytona 500 crown in 2014.
But his tenure with Hendrick was also marked by injuries. After a pair of concussions in a six-week stretch, Earnhardt sat out two races in the 2012 playoffs. Two severe wrecks during the middle portions of last year left him sidelined for the final 18 races of the season.
The time outside the car gave him a new perspective about the effects of brain injuries on athletes, and Earnhardt advocated for change in working with NASCAR to develop its concussion protocol. Just two months before his 2016 injury, Earnhardt announced that he would donate his brain for scientific research upon his passing.
Even as his rehabilitation lingered through the second half of 2016, Earnhardt expressed an interest in returning to competition. Last December, he was certified to return to the track after a test session at Darlington Raceway. Those preparations came during an offseason of personal change as well, as Earnhardt wed Amy Reimann in a New Year's ceremony.
This story will be updated.