New England Patriots star tight end Rob Gronkowski is basically an overgrown middle-schooler, and we mean that in the best way possible.No one gets more joy from playing in the NFL than Gronk, and no one has more fun off the field, either.When you combine Gronk's otherworldly athleticism with his sense of humor, you get one of the most entertaining athletes in any sport, someone who brings life to every interview he does.So, it should come as no surprise that when Gronk was asked by Bleacher Report how much he'd pay to switch his jersey number to No. 69, he was ready with a hilarious and appropriate response, saying he'd pay $69,000 for the honor:

Obviously, as a tight end, Gronkowski is not able to wear No. 69, as that is reserved for linemen. Currently, third-year offensive lineman Shaq Mason wears the number for the Patriots, but he'd probably be willing to trade with Gronk for a week if such a thing was possible.

It's not all fun and games for Gronk, though. As he tries to make a full return from injuries that plagued him last season, he is working hard to prevent them from happening again. His hard work has drawn the praise of star quarterback Tom Brady, who said he's enjoyed seeing Gronk grow this offseason (via USA TODAY):

“Gronk’s really worked hard,” Brady said on Friday. “He’s gotten older and I’m proud of him for the effort he’s put in this offseason. He always puts in a lot of effort. He’s got a great work ethic, so hopefully it really pays off for him.

“Again, it’s a contact sport, and you’ve got to prepare yourself as best you can for what we’re about to face. We put ourselves in harm way a lot. To me, you’ve got to be proactive about how you condition your body to be prepared for that. He’s done a great job of that, as have a lot of guys. Hopefully, we can make it a great season.”

Gronkowski played in only eight games last year, recording 25 catches for 540 yards and three touchdowns. However, he missed the end of the season and the Patriots' run to the Super Bowl due to injury.

As the Patriots prepare to defend their Super Bowl LI title this fall, though, a healthy Gronk will be important for Brady and the offense to operate at full capacity. Unfortunately for Gronk, that means he'll have to keep his No. 87 jersey and do some damage at his tight end position instead of moving to the line and wearing No. 69.