The Starters: Patrick Omameh, A.J. Cann
The Backups: Earl Watford, Chris Reed, Tyler Shatley, Jeremiah Poutasi
What they need: The Jaguars need someone who can compete right away as the starter for at least the left or right guard position.
I've mentioned this before in the comments of other articles, but I don't think the Jaguars are as down on their own offensive line as a lot of the fans are. They could field an offensive line right now, with who they have on the roster and be fine. That doesn't mean it doesn't need to be improved however, specifically at the guard position.
The team has Omameh who looked decent in the time he got before injury last season and Cann regressed from his rookie season, but they could definitely use another top end talent at either guard spot to push for a starting role. For the Jaguars to find this in the draft, they'll need to either look at the top of the second round or hope there isn't a run on offensive lineman and someone is still there by the time the third round rolls around. I think that whatever the Jaguars pick with the No. 4 pick will greatly influence how much emphasis the team puts on upgrading the position.