Tom Curran of CSNNE.com reports the New England Patriots and San Diego Chargers are discussing a potential trade involving unsigned restricted free agents Vincent Jackson and Logan Mankins.

Talks are described as "preliminary".

The 6-5, 240-pound Jackson is coming off a career year, catching 68 passes for 1,167 yards and 9 touchdowns, earning his first trip to the Pro Bowl. Jackson has 198 receptions for 3,400 yards and 25 touchdowns since being chosen by the Chargers in the second-round (61st overall) of the 2005 NFL Draft out of Colorado State.

Jackson has served a three-game suspension for violating the league's personal conduct policy in regards to his two DUI convictions. Placed on the roster exempt list in August, Jackson will currently need to sit out an additional three games once he reports to the Chargers or, if traded, his new team.

The NFLPA is digging into language in the collective bargaining agreement that may reduce the length of time that Jackson has to sit once he reports to a team.

Wednesday's trade of Randy Moss makes the Patriots' interest in Jackson understandable. What's not so clear is why the Chargers would be interested in Mankins.

The Chargers are currently paying left guard Kris Dielman $5.5 million in total compensation annually, and the team is close to getting right guard Louis Vasquez back from a knee injury. Unless they're looking to move Dielman after the season, adding another high-priced guard for the long-term might not be too high on A.J. Smith's to-do list, particularly with the team several months away from having to address left tackle Marcus McNeill's contract.

Prior to his decision to not sign his RFA tender, Mankins had started 87 consecutive regular season and playoff games for the Patriots, picking up Pro Bowl honors in 2007 and 2009.

A restricted free agent this off-season, the former first-round pick (32nd overall) out of Fresno State was tendered at the "First- and Third-Round" level. The club has reduced Mankins' $3.268 million tender to $1.54 million, a figure that reduces by $90,588 each week Mankins remains unsigned.

Mankins is reportedly seeking a contract that averages in excess of $8 million per season. The two sides were reportedly close to a long-term extension, but an alleged apology demand kept a deal from being reached.