NASCAR Xfinity Series at Bristol

Bristol Motor Speedway — September 17, 2021

A.J. Allmendinger
Winner
306
Laps
40
Entries
7
Leaders

A.J. Allmendinger won the 2021 NASCAR Xfinity Series at Bristol at Bristol Motor Speedway on September 17, 2021, leading 1 of 306 laps. Austin Cindric finished second; Riley Herbst rounded out the podium. The race featured 7 different leaders.

Race Details
Date
Friday, September 17, 2021
Season
2021
Leaders
7 drivers
Pos Start +/- Driver
1 10 +9 A.J. Allmendinger
2 9 +7 Austin Cindric
3 8 +5 Riley Herbst
4 2 -2 Justin Allgaier
5 16 +11 Brandon Jones
6 5 -1 Justin Haley
7 6 -1 Harrison Burton
8 17 +9 Myatt Snider
9 22 +13 Sam Mayer
10 4 -6 Daniel Hemric
11 3 -8 Ty Gibbs
12 1 -11 Noah Gragson
13 13 Jeremy Clements
14 11 -3 Brandon Brown
15 31 +16 Ty Dillon
16 32 +16 Sage Karam
17 36 +19 Joe Graf Jr.
18 39 +21 Gray Gaulding
19 14 -5 Alex Labbe
20 18 -2 Josh Williams
21 21 Brandon Gdovic
22 27 +5 Stefan Parsons
23 23 Tommy Joe Martins
24 7 -17 Jeb Burton
25 29 +4 Jeffrey Earnhardt
26 37 +11 B.J. McLeod
27 30 +3 Jade Buford
28 25 -3 Jesse Little
29 19 -10 Kyle Weatherman
30 24 -6 David Starr
31 33 +2 Spencer Boyd
32 34 +2 Carson Ware
33 38 +5 Chad Finchum
34 12 -22 Ryan Sieg
35 15 -20 Josh Berry
36 26 -10 Matt Mills
37 28 -9 Ryan Vargas
38 40 +2 Bayley Currey
39 35 -4 Landon Cassill
40 20 -20 Brett Moffitt
Model Performance

How well did the NR-Rating model predict this race? Across 12 matched drivers, the model averaged 11.6 positions off — worse than the season average of 8.5. Below Average

Pos Driver Predicted Actual Delta
1 A.J. Allmendinger 18.3 1 +17.3
2 Austin Cindric 17.0 2 +15.0
3 Riley Herbst 22.1 3 +19.1
4 Justin Allgaier 17.7 4 +13.7
6 Justin Haley 21.2 6 +15.2
11 Ty Gibbs 12.6 11 +1.6
12 Noah Gragson 23.0 12 +11.0
15 Ty Dillon 24.3 15 +9.3
26 B.J. McLeod 25.6 26 -0.4
30 David Starr 20.2 30 -9.8
33 Chad Finchum 22.1 33 -10.9
35 Josh Berry 19.0 35 -16.0

Predicted finish from NR-Rating model. Delta = predicted − actual (positive = driver beat prediction). Confidence: High Confidence = low variance (stdDev ≤ 9), Moderate = medium variance, Coinflip = high variance.

Historical Context

  • A.J. Allmendinger: has 28 career starts at Bristol Motor Speedway with a 21.0 avg finish (1 win) — the model may have underweighted this track history.
  • Ty Gibbs: was the model’s top pick based on 10 career starts at Bristol Motor Speedway with a 12.6 avg finish (1 win), finishing P11 on the day.
  • Riley Herbst: was the biggest surprise, finishing P3 vs predicted P22. Track history: 8 starts, 12.9 avg finish.

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Frequently Asked Questions

Who won the 2021 NASCAR Xfinity Series at Bristol?
A.J. Allmendinger won the 2021 NASCAR Xfinity Series at Bristol at Bristol Motor Speedway.
Where was the 2021 NASCAR Xfinity Series at Bristol held?
The 2021 NASCAR Xfinity Series at Bristol was held at Bristol Motor Speedway on September 17, 2021.