Eight-time Pro Bowl quarterback Tom Brady steered the high-scoring New England Patriots to another AFC East crown last season but turmoil in the team’s receiving ranks could pose a problem for the 2013 campaign.

Rob Gronkowski and Aaron Hernandez, the team’s twin towers of strength at the tight end position, are both under clouds, a new crew of wide receivers has been brought in to audition and Brady’s favourite pass target has been replaced.

“We’ve had a lot of turnover this year, especially at that position,” Brady told reporters about the pack of wide receivers he has been working with in organized workouts. “Really there hasn’t been anyone we’ve thrown to in any game action.”

Gronkowski, who in 2011 led the National Football League with 17 touchdown catches, underwent back surgery on Tuesday, his fifth operation in less than a year following four surgeries on his left forearm.

Hernandez, another of Brady’s favourite receivers, is being questioned by police in Massachusetts as part of a murder probe into the killing of a young man found less than a mile from his home, according to local media.

He has also been hit with a civil lawsuit by a Connecticut man who claims the Patriots tight end shot him in the face after the two left a Miami strip club in February, causing him to lose an eye.

“We’re not sure what the position is going to look like,” NFL Network analyst Charley Casserly, an NFL general manager for 16 seasons, told Reuters in a telephone interview on Thursday.

“Gronkowski is going to be out for a while and with Hernandez, we have to wait and see what happens with him.”

While it is not yet known whether Gronkowski will be ready for September’s season opener, or what the status of Hernandez will be, Casserly said the Patriots would surely suffer if the tight ends were not on the field.

“If they don’t have Gronkowski and Hernandez you don’t have a big time guy you have to defend,” said Casserly.

New England, who had the NFL’s fourth-ranked passing attack in winning their fourth straight division title, have done most of their damage throwing to the inside, but Brady’s top slot target, Wes Welker, left to play for the Denver Broncos.

Danny Amendola of the St. Louis Rams was brought in as a replacement, a speedier but less durable version of Welker.

Welker, 32, had five seasons with over 1,000 receiving yards with the Pats and three times led the NFL in receptions.

But New England got younger and faster adding 27-year-old Amendola, who missed all but one game in 2011 with a dislocated elbow and five games last year with shoulder and ankle injuries.

Casserly said Amendola could be a bigger breakaway threat, but must strike a rapport with Brady and prove his durability.

“Amendola is probably a faster guy, a little more versatile. When the Patriots want to go with two tight ends and two wide receivers Amendola can go outside and be a threat.”

Brady gave Amendola a good early review, though he conceded it takes time to develop chemistry.

“Danny has come in and he’s been fun to play with. He’s come in and worked so hard,” Brady said. “He’s diving out there for catches. He’s really done everything that we’ve asked him to do. It’s been a lot of fun.”

The wide receiver group is a mix of rookies and free agents.

The Patriots are banking on a pair of receivers plucked from the 2013 NFL Draft — Aaron Dobson (second round, 59th overall) and Josh Boyce (fourth round, 102), both with size and speed.

Veterans brought on board to compete for a role on the team include Michael Jenkins, 30, and 25-year-old Donald Jones.

As complements to the tight ends, Casserly thinks the wide outs would be fine.

“But if they have to rely upon Dobson, Boyce and Jones, guys that weren’t there last year, that would be a significant challenge for them.”