Joe Gibbs Racing has swapped its pit-crew lineup ahead of Sunday’s opening race of the NASCAR Cup Series Playoffs, having the five over-the-wall crew members for the Nos. 20 and 54 teams trade places.

A JGR spokesperson confirmed the switch for the postseason, which is also reflected on the official NASCAR team-roster portal for Sunday’s Cook Out Southern 500 (6 p.m. ET, USA, MRN, SiriusXM, NBC Sports App) at Darlington Raceway. The change was first reported by NBC Sports.

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Christopher Bell helped JGR’s No. 20 Toyota team reach the Cup Series Playoffs for the third consecutive year. Rookie Ty Gibbs fell short of the 16-driver title-eligible field after a crash in the regular-season finale at Daytona International Speedway sidelined his No. 54 JGR Toyota and thwarted his last chance to qualify.

The personnel move bolsters Bell’s postseason prospects by providing him one of the best pit crews in the Cup Series. The No. 54 group claimed the pole position for the NASCAR All-Star Race by winning the pit-crew competition, and in July the team claimed a record with an 8.54-second stop for four tires and fuel at Richmond Raceway.

The new rosters for both teams at Darlington:

• No. 20 Joe Gibbs Racing Toyota: Blake Houston (front changer), Jacob Holmes (tire carrier), Michael Hicks (rear changer), Derrell Edwards (jack), Peyton Moore (fueler)

• No. 54 Joe Gibbs Racing Toyota: Jackson Gibbs (front changer), Nick McBeath (tire carrier), Kevon Jackson (rear changer), Braxton Brannon (jack), Ian Anderson (fueler)