Cockroach on 'The Talk' Set Upstages Sheryl Underwood

This is NOT the replacement co-host Sheryl Underwood or anyone else at "The Talk" had in mind, and yet, there he is ... Mr. Cockroach hogging the spotlight!!!

It all went down during Monday's episode as Sheryl was introducing a segment about an unruly Delta Air Lines passenger on a flight from LAX to the ATL. Little did she know there was an unruly guest in the studio ... slowly creeping in her background.

It didn't seem to bug Sheryl ... but probably only because she didn't see it. La Cucaracha was several feet behind her, silently climbing a wall on set.

"The Talk" films in the massive CBS Studio Center in Studio City, so let's be real ... there's gonna be an invading critter every now and then. This one just happened to find his key light.

Could have been much worse ... just ask former VP Mike Pence.

Then again, Sheryl might have handled it like a boss ... a la President Biden fending off that cicada last week.