How petty is Klay? This autographed 'Strength in Numbers' ball says he's pretty petty

Klay Thompson won his fourth NBA Finals in 8 years on Thursday. It takes a special breed of competitive to reach the NBA — but to become a champion several times over, and to win a fourth title after consecutive season-ending injuries? Well, that's a one-of-one player.

Thompson isn't just a one-of-one basketball player. He's a one-of-one human: Despite not being known for being petty, Thompson went at a competitor the Warriors dispatched two rounds earlier — Jaren Jackson of the Memphis Grizzlies — in his comments immediately following the victory Thursday night in Boston.

"This was a collective effort, so 'Strength in Numbers' is alive and well," Thompson said of the team's slogan after the game. "There was this one player on the Grizzlies who tweeted, 'Strength in Numbers,' after they beat us in the regular season and it pissed me off so much. I can't wait to retweet that thing. Freakin' bum."

For Thompson, "Strength in Numbers" provided extra motivation — to the point that he even signed it on a basketball with his autograph up for auction on Fanatics.com.

Klay Thompson autographed "Strength in Numbers" basketball

According to the product listing, bidding on the Wilson City Edition Basketball began June 15, 2022. The auction concludes June 27, 2022, with the price at $650 as of press time Friday. Bids are accepted in increments of $50. As the description details, the ball is hand-signed "alongside the inscription 'Strength in Numbers' and "includes an individually numbered, tamper-evident hologram that can be verified online to certify authenticity."

If you're not willing to shell out hundreds, if not thousands of dollars for an autographed basketball full of spite — it's a one-of-one itself — you can still nab all sorts of other Warriors championship gear on Fanatics.