By Steve Silverman

(CBS) The Chicago Bears become Marc Trestman’s team during minicamp.

He has to seize control, make his players understand his offensive gameplan and turn the Bears into a modern, attacking NFL team.

The Bears tried to do this in fits and starts under the old regime. They brought in a quarterback in Jay Cutler, a washed-up offensive coordinator in Mike Martz, a meat-and-potatoes offensive coordinator in Mike Martz and a stellar receiver in Brandon Marshall.

None of that worked. The Bears never had the look of an offensive team that could run with the big dogs. The Green Bay Packers, New Orleans Saints and New England Patriots stand head-and-shoulders above the rest when it comes to attacking and lighting up the scoreboard. None of those teams are complete and all have defensive deficiencies.

But they set the standards for the passing game. Teams that win championships all have passing games that can make big plays at the most important moments. The Ravens hit their biggest plays in the postseason against the Broncos, Patriots and 49ers in the Super Bowl when Joe Flacco went downfield.

The year before, Eli Manning did the same thing for the Giants in the Super Bowl against the Patriots.

That’s what Trestman is going to attempt to build. It has to start in minicamp because there simply isn’t enough time for a new head coach to establish what he wants to do without making every practice between now and the start of the season.

This is a culture change. The defensive holdovers are getting older. The old defensive symbol of this team, Brian Urlacher, is gone. The Bears have been a team steeped in a defensive identity for generations.

The hiring of Trestman has put an end to that. That’s no longer a winning way.

The evolution of pro football has turned rock-ribbed defense into a historical concept. The job of the defense is to come up with stops and turnovers at vital times in the game. Shutting down a high-quality opponent? Nobody expects that anymore. Offenses are too good and the rules favor them.

Trestman and offensive coordinator Aaron Kromer have to make sure the offensive line is up to par. That’s one of the goals of this minicamp. Trestman lives, breathes and eats the West Coast offense, but the foundation of that offense – or any other – is consistent blocking. It doesn’t matter that the Bears brought in Martellus Bennett to help out Matt Forte, Cutler and Marshall unless the offensive line plays consistent football.

The Bears addressed this situation by signing Jermon Bushrod and Matt Slauson, but now that offensive line must come together. Additional pieces will presumably be added during the draft, but the hard work begins right now.

The offense must be taught, learned and executed in a short period of time. It’s short because training camp has changed so dramatically over the years.

There is far less hitting than there was 15 years ago or more and if you can’t practice a new offense at top speed, you aren’t going to learn it as well.

That’s not just a Bears’ handicap – it impacts any team that brings in a new administration. That’s why teams have to be circumspect before making such a dramatic change.

Phil Emery was right to make the change. Under the best of circumstances, the Bears defense would have been close to last year’s level and the offense would have been mediocre if he had kept the Lovie Smith coaching administration.

Under Trestman, it seems to be an all-or-nothing kind of gamble. Even if Trestman proves to be a true NFL leader, it may take him a year or more to get his offensive system across to his players.

Bears fans should not count on 2013 becoming a watershed season. If all goes well, Bears fans will see a much better team in the second half of the season than they will the first. The 2014 season is the one where the Emery-Trestman partnership will pay dividends, but only if Trestman can start coaching his team effectively right now.

steve silverman small Silverman: Trestman Era Starts In Earnest Now

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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