The 5 biggest questions entering the 2015 NFL season

Top 5 NFL questions heading into the season
deflategate response

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Story highlights

  • NFL regular season kicks off September 10 with Super Bowl champs New England Patriots hosting Pittsburgh Steelers
  • Tom Brady's debut: October 18 vs. Indianapolis Colts, who alerted NFL of underinflated footballs in AFC Championship Game
  • A rule change on extra points could make Tim Tebow a secret weapon for Philadelphia Eagles -- if he makes final roster

(CNN)The NFL regular season begins Thursday September 10 at Gillette Stadium in Foxborough, Massachusetts, with the Super Bowl champion New England Patriots hosting the Pittsburgh Steelers. Currently, Super Bowl MVP Tom Brady won't be there because of his four-game suspension for his role "Deflategate." But when will he be back? That's one of the five biggest questions entering the 2015 NFL season.

1. When will Tom Brady take the field with the Patriots?
As of now, NFL fans will see Brady in regular-season action starting October 18 in Indianapolis against the Colts -- the team the Patriots faced in the AFC Championship Game that sparked "Deflategate." Brady, who has denied wrongdoing, was accused of knowingly using underinflated footballs for a competitive advantage.
    "I am overwhelmed and humbled by the support of family, friends and our fans who have supported me since the false accusations were made after the AFC Championship game," Brady said in a Facebook post. "I look forward to the opportunity to resume playing with my teammates and winning more games for the New England Patriots."
    Brady is allowed to practice and play in the preseason but is scheduled to miss games against the Steelers, Buffalo Bills, Jacksonville Jaguars and Dallas Cowboys. The Patriots are expected to rely on little-used backup Jimmy Garoppolo during Brady's absence.
    But the timing of Brady's regular-season debut could change depending on what happens in federal court in Manhattan. Both the NFL and NFL Players Association have filed lawsuits against each other: the NFL asking a judge to confirm its decision to suspend Brady, and the players union asking a judge to vacate the decision.
    Both sides want this resolved by September 4, prior to the start of the regular season. U.S. District Court Judge Richard Berman has urged the NFL, the union and Brady to settle. Negotiations are ongoing.
    2. Will Tim Tebow make the Philadelphia Eagles roster?
    Part of Eagles head coach Chip Kelly's offseason overhaul included signing Tebow. Remember him? The former Heisman Trophy winner was cut by the Patriots in training camp in August 2013. He hasn't played in the NFL since 2012, when he was with the New York Jets.
    But with the offensive mind of Kelly, Tebow might stick in Philadelphia. While it's unlikely he'll leapfrog Sam Bradford, Mark Sanchez and Matt Barkley for the starting quarterback job, Tebow potentially could be used as a two-point conversion specialist. In May, NFL owners approved a rule change to move the football to the 15-yard line for extra point attempts, making them more difficult rather than automatic points after touchdowns. Two-point conversion attempts will remain at the 2-yard line. The new rule could make Tebow, known for his rushing ability, a secret weapon for Kelly.
    "Tim Tebow is going to shock a lot of people because he's going to make the team," Eagles linebacker Brandon Graham said on Radio One Detroit. "And I think he can play a lot."
    3. Will Johnny Manziel return to "Johnny Football" or end up a bust?
    It wasn't exactly a stellar first year in the NFL for the quarterback known as "Johnny Football." After a rough rookie season with the Cleveland Browns that ended with a hamstring injury, Manziel's offseason included a lengthy stay at Caron Pennsylvania, an alcohol and drug treatment facility. Since leaving treatment, Manziel has moved from downtown Cleveland to a suburb. He also announced in June that he's no longer using his signature "money sign" celebration and that he's trying to close a chapter in his life and build on what he's done this offseason.
    "Actions speak way louder than words," Manziel said in June. "As much as I may have intended to do some of those things last year and really, truly wanted to, I don't feel like I was in a position personally. Now, I think I'm doing the right things and taking the right steps necessary for me to put myself in the best position possible to be exactly what this organization drafted me to be.
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    "I don't want to give up on that fact at all. I'm not giving up on the fact that they brought me in here as a first-round pick and want to see something out of me. It's not lost on me and hopefully not on the people in this locker room either."
    It's likely that Josh McCown, whom the Browns signed during the offseason, will start Week 1 against the New York Jets on September 13. However, Browns head coach Mike Pettine hasn't ruled out Manziel as the starter, saying he still can win the job based on performance.
    4. How will Adrian Peterson perform after basically having a year off?
    Peterson is 30 years old, a dreaded age for a running back. However, there's reason to think that he can return to top form on the field for the Minnesota Vikings. Peterson has had time off previously, when he suffered a torn ACL and vigorously rehabilitated to return in nine months for the 2012 season. All Peterson did then was become the seventh player to rush for 2,000 yards in a season -- finishing with 2,097, nine yards short of breaking Eric Dickerson's single-season record set in 1984. This time around, Peterson is well-rested.
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    "My body feels great," Peterson said at training camp on July 25. "Mentally, I'm stronger than I've been ever before, and I just have a different mindset when it just comes to life in general -- and football too. So with that, I know that that's going to make me a better player."
    Rehabbing his image, however, may be harder. Peterson missed but all of one game last season, having been placed on the Exempt/Commissioner's Permission List and then being indefinitely suspended last year after a child abuse case in Texas. He was accused of disciplining his then-4-year-old son too harshly with a "switch," or thin stick. The NFLPA filed a lawsuit in federal court in Minnesota on Peterson's behalf and won; the NFL is appealing the decision. Peterson was reinstated by the NFL in April and has participated at training camp.
    5. Will we see a vintage or declining Peyton Manning this season?
    Does Manning have at least one good season left in him? Last year, he showed the typical brilliance that has been custom throughout his career, but there were also questions about his arm and durability at the end of the season. In the first half of 2014, Manning was in MVP form, throwing for 24 touchdowns and five interceptions. However, in the second half of the season, his numbers dropped dramatically: 15 touchdowns and 10 interceptions. In the Denver Broncos playoff loss to the Colts, Manning was underwhelming with a quarterback rating of 75, throwing for one touchdown.
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    Manning has one of the most brilliant minds in football, and his drive to win is still there.
    "You always try to use your experience as a teacher," Manning said at veteran mini camp in June. "I've always tried to learn something from every repetition and situation -- defense, the best way to counter it. Hopefully you've got a pretty good storage file up there in your mind and in your memory that you can use to figure out kind of what works and kind of what you should do to adjust to different things."
    But the question will be Manning's health. At age 39, can he make it through a full season healthy? If he can, Manning is still one of the best quarterbacks in the game. If not, we may be seeing the last of a sure to be Hall of Famer.