Ace Sanders is in the slot. He has that "quicker than fast" way about him so he usually stays there even with the losses of Blackmon and Shorts. He lines up in the backfield sometimes but trying to play him outside would limit him a lot.
Will Blackmon and Mike Harris have both spent time in the nickel position and both have graded in the top 40 for CBs according to PFF. So both get playing time but they're a little different. Blackmon can offer pass rushing ability whereas Harris is more of a strictly coverage guy, so they interchange a bit based on what the defensive calls are.
Hope that's what you're looking for.
2014 Jaguars Mock
1. Johnny Manziel, QB, Texas A&M
2. Vic Beasley, LEO, Clemson
3. Andre Williams, RB, Boston College
4. Tyler Larsen, C, Utah State
4. Jon Halapio, OG, Florida
5. Ryan Carrethers, DT, Arkansas State
5. Denicos Allen, OLB, Michigan State
5. Jake Murphy, TE, Utah
6. Josh Stewart, WR, Oklahoma State
7. Gator Hoskins, H-back, Marshall