The ninth-year veteran has established himself as a top five quarterback in the league and has helped lead the Steelers to three AFC Championships and two Super Bowl titles.
Roethlisberger is a winner on the field where he has accumulated an 80-33 record in the regular season and is one of the toughest quarterbacks in the league, constantly facing pressure from opposing defenses and doing things that no other quarterback in the league can do to escape them.
Put Byron Leftwich or Charlie Batch under center and the Steelers go from a dynamic offense with big-time playmakers at the receiving position to a ground-and-pound conservative attack that plays not to make a mistake.
Quite simply, Roethlisberger's production cannot be replaced and the Steelers go only as far as Roethlisberger will take them.
That was evident last season as Pittsburgh's chances greatly decreased after Roethlisberger sprained his ankle against the Cleveland Browns.
Given that mobility is one of his best weapons, Roethlisberger's limited ability to move the pocket was a hindrance and took the Steelers from being one of the favorites in the AFC to a long shot behind the New England Patriots and Baltimore Ravens.
Looking at this season, Roethlisberger's role with the offense is particularly important this season as the Steelers are likely to be without Rashard Mendenhall for the start of the season, according to RotoWire.com (h/t Yahoo! Sports).
Isaac Redman and his physical style of running should be just fine behind a revamped offensive line (h/t Scott Brown, triblive.com). But he should not be the workhorse back that Mendenhall was as the carries should be shared in a running back by committee approach.
While the Steelers have a couple of potentially dynamic running backs in Chris Rainey and Baron Batch, both are role players and will compete for the third-down back position.
Without a dominant backfield, the Steelers will once again lean on the pass, and that is how Todd Haley should gear the offense. Roethlisberger is still in the prime of his career and he needs to carry the offense.
As it stands now, the offense is built around the passing game.
Pittsburgh has one of the best deep threats in the game with Mike Wallace, and Antonio Brown had a breakout season last year and he should build off that success.
Emmanuel Sanders rounds out a very talented trio as he will have the slot position locked down now that Hines Ward has retired, and Jerricho Cotchery provides a veteran presence for the four-wide receiver sets.
Though the Steelers lack size with the receiving corps, they do have tremendous speed and quickness. That will make them hard to defense against.
Roethlisberger will have more opportunities to find these receivers this year as the offense will become more balanced and play to the team's strengths rather than trying to force things.
This means that Pittsburgh will use more of Heath Miller in the middle of the field, and Rainey will be a new addition as a potential screen option on passing downs.
With so many options at Haley's disposal, the playbook will keep defenses guessing as the Steelers use all of the talent available in the passing game.
For everything to operate smoothly, though, it depends on Roethlisberger and how much he follows the new scheme as opposed to falling into his old habits.
Roethlisberger will be required to get the ball out quickly. He'll have to take the safe options which could include dumping the ball off to the tight ends or running backs. No longer can he focus on exclusively looking for the big play.
That is not to say that Roethlisberger should no longer make plays outside of the pocket. He can't change what makes him elite. However, he needs to play within the system and if he does, his numbers should explode.
Last year's training camp was the best of Roethlisberger's career. He looked sharp, got the ball out quickly and was accurate. But things broke down during the season.
Roethlisberger's best two games were when he played more of the drop back and throw style of play against the Patriots and Tennessee Titans. In those two games, he completed over 71 percent of his 84 passes attempted for 593 yards with seven touchdowns and two interceptions.
The 3.5:1 touchdown to interception ratio was much better than the 1.17:1 ratio that he had for the other 14 games.
If that Roethlisberger can show up this year and play within the system that Haley implements, not only should he have the best season of his career, but he will join the ranks of the elite passers of the league. And he'll carry the Steelers to a division and possibly Super Bowl title.
Football is the ultimate team game, but if any player on the field has to carry the load it is the quarterback. Luckily for the Steelers, they have one who is up for the task.
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