Travis Kelce and Christian McCaffrey are used to playing against each other on NFL fields, but on Wednesday, they joined forces for a change ... and filmed what appears to be a fun commercial in Los Angeles.

The Chiefs tight end and the 49ers tailback teamed up for a shoot in Long Beach for Lowe's ... hitting one of the hardware giant's stores to appear in front of cameras.

McCaffrey looked as buff as ever as he cruised through the set in a red and blue No. 23 jersey ... and check out his left hand, he was also seen sporting a new ring on his finger after marrying Olivia Culpo earlier this month.

Kelce, meanwhile, looked good too ... rockin' a smoldering look on his face as he donned his No. 87 Lowe's uniform.

The guys did show up to the shoot at the same time ... although it's unclear if they ever appeared on the screen together.

It's actually not the first instance the on-field rivals have become teammates ... they shot a Lowe's commercial together last year as well. Dak Prescott was also in that one ... but there was no sign of the Dallas Cowboys quarterback on Wednesday.

No word when the ad will air ... but fans won't have to wait too long to see them on television -- the NFL's regular season kicks off in about two months!