NASCAR star Kyle Busch is giving credit where it's due ... telling TMZ Sports he can only applaud his wife, Samantha, for ruthlessly trolling him over "inches" last week.
In case you missed it -- one of the closest finishes in NASCAR history went down in the Ambetter Health 400 at Atlanta Motor Speedway last Sunday ... with Busch, Daniel Suarez and Ryan Blaney being neck and neck (and neck) right up until the checkered flag.
The 2015 and 2019 Cup Series champion addressed his third-place finish after the race -- going to Instagram and admitting he "Needed a couple inchesud83dudccf" in order to come out on top .