Positives of the potential move
The first benefit of signing Marcus Mariota, if he is brought in as a backup, is the simple fact that he is a better quarterback than Mike Glennon, Deshone Kizer, or Nathan Peterman. There is no need to do a statistical comparison or talk about resumes for this point at it is just a fact. Glennon, Kizer, and Peterman are just not very good at football and no matter how highly Jon Gruden may think of Peterman, he would take Mariota over any of them in a heartbeat.
The second positive in signing Mariota is that of the quarterbacks on the market who would be willing to join a team as backup, he is the best of the bunch. There are of course better QBs on the market like Teddy Bridgewater but he is almost certainly looking for a starting role after biding his time in New Orleans.
Jameis Winston is a free agent as well and given Tampa Bay’s lack of commitment to him he could sign elsewhere but will be looking to start as well. Realistic candidates for a pure backup are the likes of Case Keenum, Kyle Allen, Brett Hundley, and several others that Mariota is head and shoulders better than.
If Gruden sees whoever is brought in to the QB room as true competition to Carr then Mariota fits that bill as well as a former starter with top-five draft pick pedigree. There is little question that Carr is a better pure QB and a far more prolific passer than Mariota but Gruden could see potential that he could tap in to and unlock. Gruden may also see Mariota’s athleticism and willingness to run with the football as another dimension that could further unlock the offense.
Carr is an excellent athlete as well and has used his legs to extend plays but he has rarely been a willing runner but having Mariota around could inspire him to do so more often. That athleticism could also allow Gruden to dig a little deeper in to his bag of tricks design specific packages for a QB with Mariota’s skillset.
Now let’s take a look at the possible negatives of this move.