Dale Jr. and Matt Kenseth through the years

Dale Earnhardt Jr. and Matt Kenseth have had intertwined careers in stock-car racing, climbing the NASCAR ladder and entering the premier series as rookies in 2000. With the 2017 season drawing to a close, Earnhardt is set for retirement from full-time driving and Kenseth says he'll take a break from competition.

With both careers in their twilight, let's take a look at Matt Kenseth and Dale Earnhardt Jr. together through the years.

Earnhardt won two titles in what is now the NASCAR XFINITY Series, edging Kenseth, who finished second in 1998 and third in '99. Both made their moves to the Monster Energy NASCAR Cup Series in 2000, and they contended for wins out of the gate.

Here, Earnhardt's No. 8 Chevrolet battles alongside Kenseth's No. 17 Ford in April 2003 at Talladega Superspeedway. Earnhardt prevailed in this race. Kenseth won the season-long fight in 2003, securing his only premier-series title while was Earnhardt third in the standings.

Kenseth and Earnhardt share a moment in 2005 at Phoenix Raceway. The two forged an early bond that continues today.

'I was just trying to do well,' Earnhardt said of the early stages of his career. 'I was really nervous coming up into the ranks, but Matt engaged me and we became friends through conversations with him really quickly.'

Earnhardt races ahead of Kenseth at Michigan International Speedway in 2006.

Kenseth and Earnhardt joke around in the garage during the 2006 season. Kenseth wound up second in the standings that year, while Earnhardt was fifth in the series points.

Earnhardt transitioned to Hendrick Motorsports to drive the No. 88 Chevy in 2008, while Kenseth remained a mainstay at Roush Fenway Racing in the Ford camp.

Kenseth and Earnhardt chat with team owner Rick Hendrick on the grid at New Hampshire Motor Speedway in 2010.

Both Kenseth and Earnhardt had new looks for the 2012 season. Kenseth finished seventh in the standings, with Earnhardt 12th.

Earnhardt and Kenseth in 2013, when Kenseth finished second in the overall standings to Jimmie Johnson.

Earnhardt, seen here with Kenseth in 2014, reflected on his friend's personality near the end of the 2017 season.

'All us drivers have terrible egos and we can hardly stand each other and being around each other sometimes, but I’ve never felt that way about Matt,' Earnhardt said. 'Matt has never done anything where I have felt like he was inflating his ego.'

Kenseth joined Joe Gibbs Racing in 2013, changing his number from 17 to 20 and his manufacturer association from Ford to Toyota. Shown here alongside Earnhardt's No. 88 at Talladega in 2015, Kenseth's ride had some familiarity with DeWalt sponsorship carrying over from team to team.

Earnhardt and Kenseth chat in the Martinsville Speedway garage area during the 2015 season.

Kenseth and Earnhardt take time out in Las Vegas with Drew Carey, who hosted Champion's Week ceremonies after the 2015 season.

Kenseth and Earnhardt share a laugh on pit road at Charlotte Motor Speedway in 2016.

The looks of Earnhardt's No. 88 Chevrolet and Kenseth's No. 20 Toyota for their final season together. Here, they race side-by-side in October 2017 at Kansas Speedway.

Kenseth and Earnhardt shake hands before racing at New Hampshire Motor Speedway in September 2017. No matter what the future holds for the two in 2018 and beyond, they will forever be linked by their standout parallel careers.