Gronkowski to have back surgery

New England Patriots star tight end Rob Gronkowski will undergo back surgery, his agent confirmed Thursday.

The procedure will be performed by noted spine specialist Dr. Robert Watkins in mid-to-late June, a source told ESPN NFL Insider Adam Schefter.

It's yet another trip to the operating room for Gronkowski, who recently underwent a fourth surgery on his broken forearm.

Gronkowski's agent, Drew Rosenhaus, told the "Joe Rose Show" on 560 WQAM radio in Miami that his client's recovery time from the back surgery will be "very comparable to the amount of time he would miss with the arm surgery."

Gronkowski's estimated recovery time from the arm surgery, which took place May 21, was set at around 10 weeks, assuming there are no setbacks.

Rosenhaus described the back surgery as minor and referred to it as "killing two birds with one stone" during his interview with WQAM.

Although the back surgery was characterized as a "preventative-maintenance" procedure by Rosenhaus, a league source told ESPN that Gronkowski definitely will not be ready for the start of training camp in late July.

Rosenhaus also confirmed that Gronkowski's current back injury is not related to a previous operation in 2009 that forced the two-time Pro Bowler to miss his entire junior season at the University of Arizona.

The reason for the two-week wait for surgery, a league source told ESPN, is a precautionary measure to ensure the risk of infection, which resulted in Gronkowski undergoing his fourth forearm surgery May 21, is not a factor.

With Gronkowski sidelined, tight end Jake Ballard has looked sharp in each of the media-accessible OTAs, showing limited signs of restriction nearly 16 months after originally suffering a knee injury.

Ballard has shown reliable hands to go along with his big frame (6-foot-6, 275 pounds), and he should make a difference as a blocker when the pads come on.

The burly tight end said that while he's working toward being back to 100 percent, he's staying within the parameters of what the team's medical and coaching staff have laid out for him while he's on the field.

"I'm doing my best I can to be 100 percent, and I'm doing as much as I can, as much as they're allowing me to do out here," Ballard said. "When I'm out here I feel like I'm putting in good work and getting better."

Gronkowski originally broke his arm Nov. 18 in a game against the Indianapolis Colts. He returned to action Dec. 30 in the regular-season finale but broke the forearm again in the AFC divisional round on Jan. 13 against the Houston Texans.

ESPN's Adam Schefter and Ed Werder and ESPNBoston.com's Field Yates and Mike Reiss contributed to this report.