Five trends to look for this season 

Alex Marvez

The Wildcat attack still has claws. The 3-4 defense is back in vogue. Could a return to the single-wing offense that predates the NFL itself be next?

Dont laugh.

It doesnt matter how old the concept is or where it comes from. NFL coaches always try to catch the opposition off guard with a new wrinkle while often implementing the most innovative ideas from another squad with their own team.

Every year there tends to be some trend, Cleveland coach Eric Mangini said. I dont know what it will be this year, but I imagine at the end of the year, well be saying, Team X did this.

Most clubs keep those plans under wraps during the preseason. But here are five trends four involving Xs and Os, one about some NFL head coaches expected to continue when the regular season gets under way:

1. Offenses without star quarterbacks will continue to use a form of the Wildcat: For two seasons, Miami camouflaged some of its offensive weakness by stealing a page from high school and college playbooks. Running back Ronnie Brown was deployed at quarterback while either Chad Pennington or Chad Henne was split at wide receiver. A dangerous rusher, Brown also had a good enough arm that the possibility of a pass couldnt be ignored. Other NFL teams followed suit during the 2009 offseason and began using the formation to varying degrees of success.

If (defenses) take somebody out and cover the quarterback, youre giving one for one and youve gained a blocker inside, Buffalo coach Chan Gailey said.

Even though Brown is now back from a season-ending foot injury, Miami may use the Wildcat less after the offseason acquisition of wide receiver Brandon Marshall and considering Hennes expected development entering his third NFL season. The new king of the Wildcat jungle may be Cleveland. The Browns have two multipurpose threats in jack-of-all-trades Josh Cribbs and mobile backup quarterback Seneca Wallace.

The more times you get the ball in (Cribbs) hands, usually good things happen, Mangini said of the running back/wide receiver/returner.

But the more the Wildcat is run, the less frequently defenses are caught unprepared. Mangini said most units can audible to Wildcat-specific packages that get you out of playing what you traditionally play and try to get extra defenders in the box without being completely vulnerable in the passing game. They add one (blocker), you try to add (a defender). And you practice those defenses against the Wildcat plays as opposed to practicing your normal defense against a Wildcat play, which is very different.

Bills general manager Buddy Nix went so far as to call the Wildcat a gimmick. You can use it sparingly, but thatll be a passing fancy. Gailey believes the next step in the wildcats evolution could be the return to an even purer version of the single-wing offense that Glenn Pop Warner invented in the early 1900s, a system predicated on having a quarterback who can run, throw, block and handle the physical punishment inherent with all the single-wing responsibilities.

That guy is coming somewhere down the line, Gailey said. I dont know when and where. Michael Vick could have/would have been one of them. Steve Young was one in his own way. (Denver rookie) Tim Tebow might be. But the question is do you want that guy to get hit 15, 20 times a game? Youll probably need a 240-, 245-pounder to get that done.

2. Increased use of an unbalanced offensive line: Dallas coach Wade Phillips said this will be an even hotter trend than the Wildcat.

Its not talked about as much, but were running it, Phillips said. I think everyones running that some.

Two of Clevelands AFC North rivals, Cincinnati and Baltimore, like to utilize a sixth offensive lineman. The teams also fielded two of the NFLs top nine rushing attacks in 2009.

Its funny because all youve really got to do is move one spot over so youre back to being balanced, said Mangini, who is considered one of the NFLs top defensive minds. But its hard when youre used to eight million snaps where the guy snapping the ball is the center of the offense and hes no longer it. You think, That (adjustment) shouldnt be too tough, but things dont look right, they dont feel right. Its not how you practice the plays. Its getting used to looking at it.

Bengals left tackle Andrew Whitworth said the team actually didnt plan to use as much unbalanced line entering last season. But when top tight ends Reggie Kelly and Ben Utecht suffered season-ending injuries in training camp, the Bengals began repackaging tackles such as Dennis Roland and Anthony Collins as extra blockers. Last year's first-round pick Andre Smith could potentially fill the role this season if able to overcome conditioning and foot issues.

Its really what we had to do considering our tight end situation, to be able to get into a heavy run-package game plan, Whitworth said. It gives defenses a little bit of a mix, makes them move around a little bit and catches them off guard sometimes. We were able to do it because up front we had a lot of guys who understood football a lot. A lot of teams try it, but they end up blocking the wrong people or going the wrong way.

3. Unproven backups on the cheap for teams with star quarterbacks: Matt Cassel showed that an unheralded reserve could adequately replace one of the games best quarterbacks after Tom Brady went down in the 2008 season opener. But can lightning really strike twice if the Patriots, Colts or Bears lose their star QBs?

Their respective backups have zero NFL starts. They also make the minimum salary for their respective years in the league. That is part of their appeal for teams already allocating big bucks to starters. The Saints also are grooming a youngster behind Drew Brees, but New Orleans did sign eight-year veteran Patrick Ramsey to compete with Chase Daniel for the second-string spot.

4. The second 400-carry rusher since the 2001 season: It wont be a repeat by Larry Johnson, who toted the rock an obscene 416 times in 2006. Along with Clinton Portis and possibly Willie Parker in Washington, Johnson is now part of the run-by-committee approach that is the current fancy. But there are signs that some backs will be carrying heavy workloads.

Even if he maintained the same 5.6-yard average from last season, Tennessees Chris Johnson would still need 446 carries to reach his announced goal of 2,500 yards. San Diego plans to ride rookie Ryan Mathews on first and second downs. San Franciscos Frank Gore will be asked to do more after last Fridays unexpected retirement of Glen Coffee. And Minnesotas Adrian Peterson no longer has the luxury of a proven replacement with Chester Taylor leaving for Chicago.

5. Contract extensions for more head coaches: Chris Johnson and Houston wide receiver Andre Johnson werent the only ones this offseason to get rewarded for outperforming their old deals.

Pittsburghs Mike Tomlin, Arizonas Ken Whisenhunt and Rex Ryan, who has coached the New York Jets for just one season, all received extensions. Cincinnatis Marvin Lewis, who is in the final year of his contract, also continues dialogue with Bengals owner Mike Brown.

The next three coaches on deck are from the class of 2008: Baltimores John Harbaugh, Miamis Tony Sparano and Atlantas Mike Smith. Harbaugh has led Baltimore past the first round of the playoffs in both his seasons. Smith guided the Falcons to their first back-to-back winning seasons in franchise history. And the Dolphins are expected to rebound from last years disappointing 7-9 campaign with a healthier and improved roster.

In a year without a salary cap and almost every team having slashed player payroll, it would make sense for the Ravens, Falcons and Dolphins to reinvest some cash now than have Harbaugh, Smith and Sparano enter 2011 in the final year of their contracts.