Will Dwayne Allen be an upgrade over Martellus Bennett for the Patriots?

FOXBOROUGH, Mass. -- The New England Patriots will hold their first public training camp practice on July 27. As part of the lead-up to camp, I'll spotlight one position each weekday to highlight the team's personnel and some of the storylines of note.

We've covered wide receivers, offensive linemen and running backs this week, so let's move on to tight ends:

Personnel: Rob Gronkowski, Dwayne Allen, Matt Lengel, James O'Shaughnessy, Jacob Hollister, Sam Cotton

Roster locks: Gronkowski

Health report: Gronkowski, who was limited to eight games last season because of a back injury, was 100 percent in spring practices and a full participant. Can it stay that way once the pads come on? Gronkowski's career has had notable ebbs and flows when it comes to his availability as he played every game his first two seasons (2010-2011), missed considerable time the next two years (2012-2013), then played in every game but two over the next two seasons (2014-2015), before last year's dip. … Allen battled a nagging ankle injury at times last season, while Lengel was brought along slowly this spring after surgery on a re-fractured finger.

Allen over Bennett in focus. When the Patriots acquired veteran Martellus Bennett in the 2016 offseason, the sides had discussed a one-year extension that would have tied him to the team through the 2017 season. But an agreement couldn't be struck, and then this offseason, the Patriots decisively traded for the 27-year-old Allen before Bennett, 30, had signed elsewhere in free agency. Bennett had 55 receptions last season and filled in capably for an injured Gronkowski. Whether Allen will be an upgrade bears watching.

Varied options at No. 3 spot: What stands out beyond Gronkowski and Allen is the distinct variation in skill set among players. Lengel, at 6-foot-7 and 266 pounds, is more of a traditional tight end who can function as an inline blocker and occasional pass-catcher. The 6-foot-4, 245-pound O'Shaughnessy, who runs well and is an effective special teams player, falls more into the category of “move” tight end. Hollister (6-4, 239) and Cotton (6-4, 250) are closer to O'Shaughnessy's profile than Lengel's.

Stat check: Gronkowski played in 84.2 percent of the offensive snaps in 2015, when he avoided injury. In 2014, he was at a 70.3 percent clip.

Rookies in focus: Hollister and Cotton were signed as undrafted free agents. Hollister, who played in college at Wyoming, received the second-highest total of guaranteed money among the Patriots' undrafted signings ($90,000).

Quote of note: "Allen is really just a good tight end, a strong tight end in both the run and the pass game, another guy who has some vertical speed and can really push downfield; does a good job of blocking." -- Bill Belichick, in 2015, before facing Allen and the Colts.