Rob Gronkowski has been called many things, but "fiscally irresponsible" should not be one of them.

The New England Patriots tight end, who has a penchant for partying, reveals his surprisingly thrifty spending habits in his new book, "It's Good to be Gronk."

The 26-year-old says he hasn't yet touched a dime of his salary or signing bonus. Instead, he lives off endorsement money.

One doesn't exactly need to be frugal to live on $3.5 million, but with the questionable purchases that pro athletes sometimes make, it's admirable that Gronkowski has managed to avoid any major mistakes.

Here's an excerpt from the book, via MMQB:

“To this day, I still haven’t touched one dime of my signing bonus or NFL contract money. I live off my marketing money and haven’t blown it on any big-money expensive cars, expensive jewelry or tattoos and still wear my favorite pair of jeans from high school… I don’t hurt anyone (except Gord with the occasional kick to the groin), I don’t do drugs, I don’t drive drunk, I don’t break the law… I’m a 23-year-old guy just looking to have a fun time.”

After only making $540,000 and $630,000 in his first two years in the NFL, Gronkowski in 2012 signed a six-year, $53 million extension with the Patriots. That was the largest contract ever for a tight end.

While Gronkowski was injured for most of 2013, his solid 2014 campaign helped the Patriots on their journey to their fourth Super Bowl championship of the Tom Brady-Bill Belichick era. Gronkowski played 15 games, catching 82 passes and 12 touchdowns. He was named first team All-Pro for the second time.

Because of his outsize personality and large fanbase, Gronkowski has attracted several big endorsers. He's an investor in BodyArmor and on the payroll for Dunkin' Donuts, Nike and 50 Cent's new company, SMS Audio.

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