The New England Patriots have had a successful offseason, but with just 58 players officially under contract, they still have a lot of work before the season begins.

The Patriots have re-signed wide receiver Julian Edelman, tight end Michael Hoomanawanui and long snapper Danny Aiken and grabbed cornerbacks Darrelle Revis and Brandon Browner and wide receiver Brandon LaFell on the open market already, giving them one of the best free-agent hauls in the NFL.

The Patriots still need to find players at every position, though. Check out where they have the biggest needs in order of importance.

DEFENSIVE TACKLE

If Vince Wilfork is going to be released, the Patriots need a lot of help along their defensive front. There’s already too much uncertainty with Tommy Kelly and Armond Armstead recovering from health issues. The Patriots could sign a free-agent defensive tackle, draft one or two and pick up a rookie free agent after the draft.

TIGHT END

The Patriots have just three tight ends under contract (Rob Gronkowski, D.J. Williams and Hoomanawanui), so they likely will find Gronk insurance through the draft. The Patriots will fill out the position with a low-cost veteran or with an undrafted free agent.

DEFENSIVE END

The Patriots need a third defensive end to rotate with Chandler Jones and Rob Ninkovich and play on third down — unless they see second-year players Jamie Collins and Michael Buchanan sharing those roles. The Patriots could address this need in free agency (Corey Wootton or Shaun Phillips could fit), or they could use another high draft pick on a defensive end.

OFFENSIVE LINE

Will Svitek hasn’t been re-signed yet, so the Patriots could use another offensive tackle behind Nate Solder, Sebastian Vollmer and Marcus Cannon, since if the season started today, Dan Connolly probably would move to center with Cannon starting at right guard.

Starting center Ryan Wendell still is available in free agency and could be brought back. If the Patriots aren’t happy with a combination of Wendell, Connolly and Cannon, they could draft their future starting center.

SAFETY

The Patriots released Steve Gregory before free agency began, which leaves Devin McCourty and Duron Harmon as the starters, with Adrian Wilson, Tavon Wilson, Nate Ebner and Kanorris Davis as depth. The Patriots could go into 2014 with that group, but it wouldn’t be surprising to see them try to upgrade through free agency (Charles Woodson, Champ Bailey, Chris Clemons) or the draft.

RUNNING BACK

LeGarrette Blount still is available in free agency, but the Patriots might be better suited to sign a running back with better hands on the open market or through the draft. The Patriots don’t have a backup third-down option behind Shane Vereen on the roster, and they have carried at least two backfield-receiving options since 2010. It would drive fans crazy, but the Patriots could use a second-day pick on a running back with Stevan Ridley and Vereen entering contract years.

LINEBACKER

The Patriots went from having five linebackers they felt comfortable starting last season to just three after Brandon Spikes and Dane Fletcher walked in free agency. The Patriots could use a second-day draft pick to fill this need since the free-agent well is drying up.

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