Three Toyota playoff cars start from the bottom of the grid in Atlanta

HAMPTON, Ga. – Three Joe Gibbs Racing cars will start from the back of the field in today's Cup playoff opener at Atlanta Motor Speedway after suffering similar mechanical problems.

The cars of Denny Hamlin, Martin Truex Jr. and Ty Gibbs each had problems with the spark plug wires, which had to be replaced.

Due to unauthorized adjustments for today's race (3:00 p.m. ET on USA Network), all three cars will start from the bottom of the standings.

Truex's crew chief James Small told NBC Sports they had similar problems to those Hamlin's car had after he qualified last in the 38-car field on Saturday. Small said the problems in Truex's car were not as serious as the spark plug wire issue on Hamlin's car, but they were replaced as a precaution.

Small said Christopher Bell's No. 20 car has not had these problems. Bell will start 26th.

Truex was scheduled to start 22nd. Gibbs was scheduled to start 20th.

The first round includes races in Atlanta, Watkins Glen and Bristol.