If you're looking for a ray of hope on this front, while the Browns have more cap room than the Jags right now, they also have a lot of notable players hitting free agency in the next couple of years, while the Jags don't have much on that front (the one benefit to never drafting anybody good). Apart from Mack, the Browns have:

 

2015: Joe Haden, Jordan Cameron, Phil Taylor, Jabaal Sheard, Ahtyba Rubin, Buster Skrine, Jason Pinkston, Brian Hoyer, Greg Little

2016: Josh Gordon, Mitchell Schwartz, Ben Tate, John Hughes, Billy Winn

 

Some of those guys aren't that good (Pinkston, Little, Hoyer) but all of those guys are starters or key rotational players, and some of those guys are going to get seriously paid. In contrast, the Jags have: 

 

2015: Russell Allen, Roy Miller, Cecil Shorts, Alan Ball

2016: Marcedes Lewis, Justin Blackmon, Josh Scobee, Chad Henne, Andre Branch, Clay Harbor, Bryan Anger

 

No star players (unless you count Blackmon) and not a lot of guys you would hate to lose or who would require a significant financial commitment. So I think the strategy shouldn't really be to frontload, but to structure it in a way that it would interfere with the Browns signing their other players. Say if you wanted to sign him to a 4/36m contract, maybe give him an $8m dollar signing bonus and stretch out the cap hit like this:

 

2014: $3m

2015: $10m

2016: $11m

2017: $12m

 

The Jags will have more cap room than they know what to do with so I think it would be feasible, and I don't think the Browns would like having a center on the books for a double digit cap hit while they're trying to hold on to Haden, Cameron, Gordon etc. 

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