Russillo & Kanell wonder how Tom Brady and Bill Belichick will adjust now that one of Brady's favorite targets TE Rob Gronkowski will undergo back surgery this week. (1:20)

FOXBOROUGH, Mass. -- The New England Patriots' Super Bowl hopes have taken a major hit with the news that tight end Rob Gronkowski is set to undergo back surgery on Friday, according to ESPN NFL Insider Adam Schefter.

That much is obvious. Gronkowski is that kind of player.

So what now?

Multiple-tight end packages will decline: When Gronkowski and fellow tight end Martellus Bennett were both healthy, the Patriots were primarily a two-tight end offense. Consider that entering their Nov. 20 game at San Francisco (in which Gronkowski did not play), the Patriots had run 245 plays with two or more tight ends on the field, which was the second-highest total in the NFL. At that point, Patriots' tight ends led NFL tight ends in receiving yards (1,044) and were tied for second in receiving touchdowns (seven). The Patriots won't stay with that approach without Gronkowski, as the next tight end on the depth chart is Matt Lengel, who has played in one career game. Lengel is more of a blocker, and part of the reason the Patriots leaned so heavily on the two-tight end package with Gronkowski and Bennett is the dual threat they provided -- both are strong blockers and also have receiver-like skills. So this takes away a big part of the way the Patriots like to dictate matchups.

Third receiver becomes a bigger factor: With the Patriots almost certainly going away from the two-tight end package, this shines a spotlight on the team's third and fourth receivers -- rookie Malcolm Mitchell and Danny Amendola. Mitchell, a fourth-round draft choice out of Georgia, has been coming on strong lately. Look for more three-receiver packages, with either Mitchell or Amendola joining the top two receivers on the depth chart, Julian Edelman and Chris Hogan.

Running backs make up part of the equation: Offensive coordinator Josh McDaniels is as creative as they come, and with Dion Lewis returning from a torn ACL in Week 11 against San Francisco, McDaniels has tapped a unique two-running back package with Lewis and James White. In the past two games, the Patriots have used that "pony" grouping six times, often on third down, with some solid results. The presence of two running backs on the field at the same time could increase without Gronkowski, who was usually on the field on third down.

It's easy to second-guess the A.J. Derby trade: Given Gronkowski's injury history, the Patriots had to know they were taking a risk by trading tight end A.J. Derby to the Denver Broncos in October. Derby, a 2015 sixth-round draft choice from Arkansas, had led the team in receptions in the preseason and would have been the next man up in this situation. The Patriots received a fifth-round draft choice from Denver in return for Derby, who is emerging in the Broncos' offense.