On Monday, Jeff Howe of The Athletic reported the Pro Bowl tight end's absence from voluntary workouts is "about the money."
Gronkowski, 28, is due an $8 million base salary in 2018, per Spotrac. However, there are no guarantees remaining on the six-year, $54 million deal he signed in June 2012.
"We have the voluntary offseason program that starts on Monday," Patriots head coach Bill Belichick told reporters last week. "It will be heavily attended, but I know there are a couple players that I've talked to that have other commitments, but that's the way it always is. So, not really anything new there."
Gronkowski is yet to formally commit to playing in the 2018 season. He told reporters he would "sit down in the next couple of weeks and see where [he's] at" following New England's Super Bowl LII loss to the Philadelphia Eagles on Feb. 4. While it remains unlikely he would retire, Gronkowski remains a coveted multimedia figure who could make a transition to film or even WWE should he hang it up.
There have been numerous reports of tension between Gronkowski and Belichick during the offseason. Karen Guregian of the Boston Herald reported Belichick ripped the tight end for his adoption of the "TB12" diet used by quarterback Tom Brady. Friction between Belichick and Brady, particularly over his trainer, Alex Guerrero, had been a major storyline this offseason.
Brady is not attending voluntary workouts either, according to Jeff Darlington of ESPN.