By Matt Dolloff, CBS Boston
BOSTON (CBS) -- It's time to kick off another summer of training camp for Tom Brady and Bill Belichick. And for the fifth time together, they will enter camp with the Patriots as the defending Super Bowl champions.
The Patriots will begin 2017 as the favorite to win yet another Lombardi Trophy, with some even going so far as to predict an undefeated season. But despite the team's status as the undisputed best team, that doesn't mean they won't have a shortage of interesting stories in training camp.
It remains to be seen how Brady will perform as he hits the treacherous age of 40, how the Patriots will deploy players at the skill positions, or how the newcomers on defense will fit into the team. Here's a closer look at five of the most intriguing stories to watch at Patriots training camp this summer:
Brady at 40
Tom Brady is always the No. 1 Patriots player to watch at all times. But this season it gets as interesting as ever for the five-time Super Bowl champion, because he finally hits the big 4-0 - and, as some assistant coaches are predicting, this will be the time he finally declines.
Brady is coming off the greatest comeback in Super Bowl history and looked great in minicamp, so there's little reason beyond his age to believe that he will show cracks in the armor. That will be especially hard to gauge during training camp and the preseason. But many who cover the Patriots this time of year watch the quarterbacks particularly closely, and it will be interesting to see if anyone notices slippage in areas like strength and accuracy, in addition to Brady's usually-impeccable decision-making.
It won't become too clear how Brady's age-40 season will go until the games start to count and they are played at full speed. But another preseason of slinging the ball as smartly and accurately as ever would go a long way for Brady to show his ever-resilient critics that he's not falling off that cliff just yet.
Butler vs. Gilmore
New England boasts one of the NFL's most dynamic 1-2 punches at cornerback in Malcolm Butler and high-priced free-agent Stephon Gilmore. But one of the team's biggest questions is how they plan to use them.
The Patriots face a lot of big, talented receivers in 2017, which is likely why they acted aggressively and decisively to add Gilmore to the roster. The 6-foot-1, lengthy Gilmore will probably line up against players like Mike Evans, Kelvin Benjamin, Demaryius Thomas, and others, while Butler would be matched up against smaller, quicker wideouts.
However, that kind of plan isn't necessarily set in stone. Nothing is with Belichick. It's possible that Gilmore (or even Butler) ends up facing each opponent's best receiver regardless of physical attributes. But the Patriots' need to figure out the cornerback configuration is a good problem for Belichick to have.
After winning Super Bowl LI, the Patriots finally proved they were capable of playing championship football without Rob Gronkowski on the field. All they've done since then is add Brandin Cooks and multiple new running backs to the depth chart. So how does the 28-year-old All-Pro tight end fit into the lineup now?
Gronk is coming off the third major back surgery of his career, which should once again raise questions of how he will perform (and whether he will stay healthy) in 2017. He has come back from major injuries to be the same old Gronk before, so it's possible that happens all over again - but he can't exactly survive major offseason surgery forever.
Even with Cooks in the fold, it's likely that Gronk remains the biggest scoring threat in the Patriots offense - certainly in the red zone. He also has incentives in his new contract to stay on the field as much as he can and excel. But coming off another back surgery and entering a crowded depth chart, Gronk's place in the 2017 Patriots offense is something to keep an eye on.
Odd men out at receiver, running back
What made the addition of Cooks to the Patriots' receiving corps extra surprising was that the team appeared set at the wide receiver position. Cooks joins Julian Edelman, Chris Hogan, and Malcolm Mitchell as virtual locks to make the roster, while special teams ace Matthew Slater also counts as a receiver.
Add a recently restructured Danny Amendola to the mix, and the Patriots have at least six viable receivers on the roster. It's possible that the Patriots rotate that deep group and cut ties with recent draft picks/free agents like Devin Lucien, Austin Carr, and Cody Hollister, but a surprise trade or cut can't be ruled out at that position.
The Patriots also have a crowded depth chart at running back. James White and Dion Lewis are back, as is special teamer Brandon Bolden. But with Mike Gillislee and Rex Burkhead joining the mix, it's unlikely that Belichick will roll with that many backs to start the season. Bolden could be on the bubble, and it's unclear whether Belichick would even want as many as four running backs on the roster.
Questions on the front-seven
The Patriots defense played great for Belichick down the stretch in 2016, and made a handful of massive plays to help spur the Patriots' comeback win. But entering 2017, there's more uncertainty than people may think - especially up front.
Trey Flowers looks like a rising star at defensive end after a great second half and clutch Super Bowl last season, but it remains to be seen how he will perform now that opposing offenses will be keying on him. It's also uncertain what the team will get out of defensive end Kony Ealy, whom the Patriots acquired by simply moving down eight picks in the draft. The Pats have a good group at defensive tackle with Alan Branch, Malcom Brown, and Vincent Valentine, but will need one of the latter two to step up if Branch can't match his strong performance from last year.
At linebacker, there's no question at the top with Dont'a Hightower. But after him is where it gets dicey. It's unclear who will seize the No. 2 role between David Harris, Kyle Van Noy, Shea McClellin, Elandon Roberts, and Jonathan Freeny - and it's unlikely that all of those guys will even make the team.
What's on your list of storylines to watch in training camp this season? Share your thoughts in the comments.
Matt Dolloff is a writer/producer for CBSBostonSports.com. Any opinions expressed do not necessarily reflect those of 98.5 The Sports Hub, CBS, or any subsidiaries. Have a news tip, question, or comment for Matt? Follow him on Twitter @Dolloff985 and email him at email@example.com.
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