This week, it has become a foregone conclusion that Jon Gruden will be the next head coach of the Oakland Raiders; it's only a matter of time.

However, there appears to be some real concern about how his relationship with Pro Bowl quarterback Derek Carr will work out given his aggressive coaching style, according to Mike Florio of Pro Football Talk.

Per a league source, there’s a real concern that Carr won’t be able to put up with Gruden’s style for very long. Gruden will ride him and needle him and yell at him and criticize him and ride him some more. Carr will have to learn how to deal with that, or Carr won’t last.

Gruden has built a strong reputation as a brash head coach known to get on his quarterbacks quite roughly. At this point, it appears the organization is concerned if Carr will have the mental fortitude to withstand that type of coaching style.

It is still quite early in the process, but this will be a key factor in determining if Gruden's return to Oakland will be successful early on, and possibly long-term. Carr has already been labeled as their franchise quarterback, inking a five-year, $125 million contract last June.

Nonetheless, this is certainly something to keep an eye if the Raiders do ultimately bring Gruden on board.