JOLIET, Ill. — In the final race before the NASCAR XFINITY Series playoffs, Justin Allgaier let it all hang out in scoring his second win of the season at Chicagoland Speedway on Saturday afternoon.

The Riverton native and JR Motorsports driver led the final 15 laps of the TheHouse.com 300 after a daring three-wide move on a late-race restart saw him blow past Monster Energy NASCAR Cup Series regulars Erik Jones and Ryan Blaney.

Allgaier cleared the duo and never looked back as Jones and Blaney crashed behind him, later holding off regular season champion Elliott Sadler and another Cup star in Kyle Larson to score his fifth-career series win and second at Chicagoland.

Saturday’s victory puts Allgaier second in the playoff seedings, with the five bonus points he earned lifting him past Sadler and putting him only two points behind rookie William Byron entering the postseason.

“It’s incredible, I’ve gotten a win here before … but that was on fuel mileage and today, these guys did an awesome job.” Allgaier said. “There is nothing cooler than winning at home.”

“I wanted it really bad. I felt like after practice that we didn’t have the best car … but this team persevered throughout the course of the day. Coming down towards the end, I didn’t feel like we had a shot; we had a top-five car, maybe. On those late race restarts, though, I got some great launches. We have a great shot to go to victory lane a lot in these playoffs; we have a lot of good momentum and man, we want to go to Homestead and have a shot.”

After defending race winner Erik Jones won the pole, swept the first two stages and led a race-high 93 laps, it looked all but certain that he would take the checkered flag in the Windy City.

However, a pit road speeding penalty during the second stage break saw Jones and third-running Ryan Blaney fade to the back of the field, while Cole Custer and Kyle Larson did battle throughout the second half of the race.

A caution for a spinning Brandon Jones with 51 to go set up a restart in which Blaney surged to the front, leading the next 28 laps, but a second yellow for a spin by Daniel Saurez with 18 laps left saw all the front runners come down pit road for their final services of the afternoon.

Jones won the race off pit road, while Larson got hit with a speeding penalty on exit that dropped him outside the top 10 while Jones and Blaney set themselves up on the front row.

Racing resumed with 15 to go and saw Allgaier power to the apron, pushing Jones up into the second groove and forcing the front-runners three-wide into the corner. At the exit of turn two, Jones pushed up the track and into the side of Blaney, sending both of them into the wall as Allgaier escaped with the lead.

The next caution came with 11 laps left when Ryan Reed went around, leaving a frantic eight-lap shootout to decide the winner. Allgaier led the field back to the green flag with teammate Sadler in second.

But as the field took the green flag, Jones made a three-wide push to the outside just before the start-finish line, drawing a black flag for a restart violation that dropped him out of contention to challenge Allgaier for the win.

In the final laps, a charging Larson drove his Chevrolet back to second, but the Chip Ganassi Racing driver ultimately finished one position short of his target.

Elliott Sadler finished third and was officially crowned as the regular season champion, after locking up the honor — as well as the 15 bonus points that came with it — last week at Richmond Raceway.

A pair of Richard Childress Racing teammates, Daniel Hemric and Austin Dillon, completed the top five.

Matt Tifft crossed the line sixth ahead of Cole Custer, Ty Dillon, Blake Koch and Darrell Wallace Jr., who was making his first XFINITY start since Pocono in June.

Brendan Gaughan and Michael Annett finished 13th and 15th, respectively, to secure the final two berths in the 12-driver playoff field. They edged out Dakoda Armstrong, who struggled all day and came home in 16th.

The NASCAR XFINITY Series opens its playoffs with the VisitMyrtleBeach.com 300, Sept. 23 at Kentucky Speedway (8 p.m. ET, NBCSN, PRN, SiriusXM).

Full race results can be viewed on the next page…