The Titans are the last team to sign their first round pick for the 100th straight year*. The report is that the hang up is the offset language- meaning they are arguing over whether or not the Titans would have to pay the 4th year of his contract if they cut him before that year and he signs with another team. Michael David Smith over at PFT wrote a piece this morning explaining that the 4th year offset is almost never an issue for quarterbacks.
Listen, if the Titans are at the point where they feel like they need to cut Mariota after year 3, whether or not they have to pay him the full amount for that 4th year is going to be the least of their concerns. They will be a whole lot more worried about how to get fans to care abouta team that hasn't won anything in a long time.
The Titans have actually have some momentum nationally with the drafting of Mariota. Why they are trying to ruin it by dragging out finishing his contract is beyond me, but hey, it's the Titans. What else would you expect?