The Rock Lets a Finger Slip ... 'Saluting' Kevin Hart

1/18/2017 6:46 PM PST

Dwayne "The Rock" Johnson got busted giving Kevin Hart the bird on live TV, but to be fair ... Kevin kind of had it coming.

Hart had just finished thanking all of his co-stars for winning favorite comedy performance in "Central Intelligence" on the People's Choice Awards ... but gave the reverse of a shout-out to The Rock. 

The Rock laughed it off, but then decided to pay Kevin back right before the camera cut away ... a split second too late.

The Rock won an award for Favorite Premium Series Actor a few minutes later for his role on "Ballers."