The Patriots signed Gronkowski to a six-year, $54 million contract extension earlier this summer.
He has two years left on his rookie contract, a four-year, $2.78 million deal that included a $540,000 base salary this year as well as roster bonuses paid out for each game amounting to $104,000.
He's due a $630,000 base salary and $200,000 more through workout and roster bonuses next season.
The Patriots structured Hernandez's rookie deal due to a history of failed drug tests for marijuana at the University of Florida.
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