Potential Gronkowski absence leaves a hole

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On Tuesday, Rob Gronkowski will undergo his fifth surgery since November.Unlike his other four surgeries since November, Tuesday’s back surgery could sideline Rob Gronkowski through much of training camp if not the beginning of the regular season. If Gronkowski isn’t ready for Week 1, here are three reasons the Patriots should be worried.

The Brady-Gronk Connection

Over the last two seasons, Tom Brady has almost eight times more touchdowns than interceptions when throwing to Gronkowski. To all other targets, Brady has only about 2.5 times more touchdowns than picks.

Tom Brady Passing By Target
Last 2 Seasons (Including Playoffs)

The Brady-Gronkowski connection doesn’t just produce touchdowns. Since his rookie season in 2010, Gronkowski has caught 72.2 percent of his passes from Brady, tying the duo with Jason Witten and Tony Romo for the best completion percentage of ANY QB-TE or QB-WR combo over the last three seasons.

Gronkowski is by far the most productive receiving option returning to a Patriots team that has already lost Wes Welker, Brandon Lloyd, Danny Woodhead and Deion Branch this offseason. Even if Gronkowski is back for Week 1, Brady will start the season season missing teammates who accounted for more than 62 percent of his completions from last season.

League Leader

In just three seasons, Gronkowski has already totaled 38 receiving touchdowns, the most in the NFL over that span. In league history, only two players had more touchdown catches in their first three years: Jerry Rice and Randy Moss.

Gronkowski does most of his damage in the red zone, where he leads the league with 29 touchdowns since 2010. The only players with more red-zone targets than Gronkowski since his rookie year are All-Pro wide receivers Larry Fitzgerald and Roddy White.

But Gronkowski isn’t just a threat near the end zone. Since his rookie year, Witten is the only tight end with more receiving yards than Gronkowski, but Gronk ranks first at his position in yards per reception and yards after the catch.

Getting Physical

While Gronkowski’s back and forearm issues shouldn’t affect his size or his hands, his offseason surgeries threaten his physicality, which is arguably unmatched among the league’s current tight ends.

At 6’6” and 265 pounds, Gronkowski is an important part of the Patriots ground game. Last season, New England averaged 4.4 yards per rush with Gronkowski on the field compared to 3.9 yards per carry with him on the sideline.

And Gronkowski’s size and speed make him one of the game’s most difficult targets to bring down in the open field. In his three NFL seasons, Gronkowski has averaged 2.54 yards AFTER contact per reception. The next-best figure by a wide receiver or tight end is Jermaine Gresham’s 2.30.