By Steve Silverman-

(CBS) Free agency got off to a roaring start and the movement made by the Bears coupled with their performance on Draft Day will determine whether head coach Marc Trestman has a winning hand to play once training camp begins in the summer.

The Bears addressed their biggest need with the signing of Jermon Bushrod to play left tackle. Bushrod is a sensational pass blocker who made the Pro Bowl after the 2011 season after giving up just three sacks. He was not quite up to that level last year, but he is a solid pro who maintains his balance even when going up against bull-rushing defensive ends.

Tight end Martellus Bennett is an interesting addition who is coming off a solid year with the New York Giants after four disappointing seasons with the Dallas Cowboys.

Bennett – the self-styled “Black Unicorn” – is clearly an interesting character who enjoys life outside of the NFL environment. His new deal with the Bears allows him to live the good life no matter how many linebackers he blocks and how many balls he catches.

Bennett may not be the sure upgrade that Bears fans are hoping he will be.

General manager Phil Emery needs to add another offensive lineman in the draft and get younger on defense, so there is still much to do if the Bears want to get better.

The same holds for the Bears’ rivals in the NFC North. Here’s an assessment of the free-agent moves made by their division rivals in the early stages of free agency.

Detroit Lions – If you are familiar with the brand of football the Lions play, you might ask yourself why any talented free agent would give the Lions and head coach Jim Schwartz any serious consideration. While Schwartz’s demeanor on the sidelines and his coaching style is often regrettable, his players love him Monday through Saturday.

He’s calm, reasonable and he has a sense of humor and he is a good guy to play and work for six days a week. It’s his Sunday coaching that’s an issue.

That said, the Lions made two solid moves by adding running back Reggie Bush from the Dolphins and safety Glover Quin from the Texans.

The Lions were a playoff team in 2011 when they had a running game to take the heat off strong-armed Matthew Stafford. They didn’t have it last year and they were a last place team in the NFC North.

Bush rushed for 1,086 yards in 2011 with the Dolphins and had 986 yards last year. He is a very capable receiver. Bush is going to get his job done when he gets the blocking and can accelerate through the hole. He’s not going to make yards on his own.

Quin is a hard-hitting safety but he’s not a ball hawk. He had two interceptions last year and he has just five in his four years with the Texans. He’s a solid player, but he’s not a difference maker.

Green Bay Packers – The Packers have yet to bring in any new players, but head coach Mike McCarthy knows that Aaron Rodgers would be happier and more effective if he didn’t have to do everything all by himself on an every-game basis.

That’s why the Packers are still in heavy discussions with Steven Jackson of the Rams. Jackson is a thoroughly professional running back who may have slowed down a half-step but would be a major upgrade for the Packers.

There’s little doubt that Jackson could once again go over the 1,000-yard mark if he pulled on a green and gold jersey since he had 1,042 yards last year. However, could Jackson still get to the 1,416-yard mark he reached in 2009? That seems unlikely for a running back who has absorbed nine years of NFL pounding.

If the two sides can reach an agreement on the finances of the deal, Jackson will be a Packers running back next season.

Minnesota Vikings – The Vikings made an important move when they re-signed right tackle Phil Loadholt on Tuesday, but they made big headlines earlier with their decision to trade game-changing wide receiver Percy Harvin to the Seahawks.

Harvin had a difficult time staying healthy with the Vikings. He only played in nine games last year and the offense suffered dramatically when he wasn’t in the lineup.

However, Harvin was unhappy with the organization so they traded him to Seattle for first- and seventh-round picks this year and a middle-round pick next year.

Running back Adrian Peterson is happy to get Loadholt back, but he is reportedly seething over the loss of Harvin.

The loss of Harvin’s instinctive ability as a receiver and a return man will hurt them badly. Green Bay free agent Greg Jennings will be visiting the Vikings today and he would help offset the loss because of his consistency and route-running ability when healthy.

steve silverman small Silverman: Bears, Lions Make Biggest Moves In NFC North In Free Agency

Steve Silverman

Steve Silverman is an award-winning writer, covering sports since 1980. Silverman was with Pro Football Weekly for 10 years and his byline has appeared in the Wall Street Journal, Playboy, and The Sporting News. He is the author of four books, including Who’s Better, Who’s Best in Football — The Top 60 Players of All-Time. Follow him on Twitter (@profootballboy) and read more of his CBS Chicago columns here.

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