Elliott Sadler has competed in 22 full-time seasons in NASCAR, and the next seven Xfinity Series races represent his final chance to win a championship.

Sadler knows his life as a dad won't be defined by whether he wins a championship, and that his kids don't really care if he wins the title, but for the 43-year-old driver, not winning a title would certainly be an unwelcome line on his racing résumé.

"If we're not able to win a championship, it definitely will be a scar in my mind of not being a NASCAR champion," Sadler said.

Yet he doesn't feel as much pressure going into his final couple of months as a NASCAR driver before he concentrates on his life as a dad and a coach. He certainly isn't the favorite; Justin Allgaier (five wins) and Christopher Bell (four) carry that tag as the NASCAR Xfinity Series playoffs begin Friday night at Richmond Raceway.

"Honestly, I'm relieved," Sadler said. "I actually feel better because we know it is my last one. We can throw caution to the wind, we can take chances, we can be aggressive. I tell my players all the time, 'We're going to leave it all on the field.'

"Let's get our best effort out there, let's be aggressive and see what happens, and we can look at each other at Homestead [and say] yes we did or no we didn't."

Sadler has come close to a championship. He finished second in the Xfinity Series standings in 2011, 2012, 2016 and 2017. Last year, Sadler had a great car and felt he had a shot to catch JR Motorsports teammate and eventual champion William Byron, but a tough fight for position with Ryan Preece -- who was between them -- stymied those efforts.

Sadler hasn't won a race since September 2016 at Kentucky. He has won an Xfinity race at only one track (Phoenix, in 2012) that is among the seven in the Xfinity playoffs.

"Not winning a championship would be a huge void in my life," Sadler said. "It really would be something that coulda, woulda, shoulda, wish, had the opportunity, maybe didn't capitalize on it. Last year really, really hurt.

"We were in position to win that championship. I don't know that I'm 100 percent over it yet."

Allgaier and Bell are the only two drivers with multiple wins this year who are in the playoffs, and they each have at least a 20-point lead on the rest of the field, thanks to playoff points. The other 10 drivers enter the playoffs separated by just 11 points.

"Definitely Justin and Christopher are by far the favorites; they have shown that [with] nine wins between them," Sadler said.

"I don't have the security I've had the last two years as far as the points are concerned. ... I don't have that cushion, so maybe [I have] a little bit more pressure on us the first round."

The Xfinity playoffs consist of two three-race rounds (Richmond-Charlotte road course-Dover and Kansas-Texas-Phoenix) with four drivers eliminated after each round, creating a four-driver, best-finish-is-champ scenario at Homestead.

Five drivers have separated themselves from the pack when looking at top-5s: Allgaier (with 15), Bell (14), Sadler (13), Daniel Hemric (12) and Cole Custer (11). No one else in the playoffs has more than four top-5s this year.

"We've done our job this year; we've executed well," Allgaier said. "Until we get a win [in a round] or until we've got enough points, somebody can pass me. I'm not going to be super-pumped about it until we get to that point."

Bell wasn't too thrilled after the last regular-season race at Las Vegas, feeling he wasn't good enough to beat Ross Chastain to win. That wasn't a typical sentiment during the year, however, as his Joe Gibbs Racing team often battled it out with JR Motorsports' Allgaier for tops among the Xfinity regulars.

"Allgaier and myself have separated ourselves from the rest of the field, so to speak, as far as the points go," Bell said. "I just need to maintain on that and continue to win races. I've got to win more."

Custer won at Homestead last year, so if the Stewart-Haas Racing driver can be among the four finalists, he feels good.

"Obviously, you've got to win Homestead to win the championship, but you've still got to get there," Custer said. "All the tracks that lead up to there, we're good enough to transfer through and we can probably win. You just have to have everything go right."