The Kansas City Chiefs made sure they'll have Super Bowl MVP Patrick Mahomes around as long as possible.

The quarterback agreed to a 10-year extension worth up to $503 million, according to his agency, Steinberg Sports. The deal is worth $477 million in guarantee mechanisms and includes a no-trade clause and opt-out clauses if guarantee mechanisms aren't met.

It's the richest contract in professional sports history, surpassing Mike Trout's $426.5 million deal with the Los Angeles Angels.

"Since he joined the Chiefs just a few years ago, Patrick has developed into one of the most prolific athletes in all of sports," Chiefs chairman Clark Hunt said of Mahomes, who led the franchise to its first championship in 50 years.

"With his dynamic play and infectious personality, he is one of the most recognized and beloved figures to put on the Chiefs uniform. He's an extraordinary leader and a credit to the Kansas City community, and I'm delighted that he will be a member of the Chiefs for many years to come."

The Chiefs had the 2018 NFL MVP under contract for the next two seasons but that wasn't nearly enough.

"Here to stay," Mahomes wrote on Twitter.

The contract extension starts in 2022 when the NFL salary cap is projected to be $227.5 million. However, that number could be lower depending on revenue losses due to the coronavirus pandemic and the possibility any games played this season won't have fans.

Still, Mahomes will take up a big chunk of Kansas City's cap space-around 20 percent depending on the annual contract breakdown and final cap numbers. That could potentially make it difficult for the Chiefs to pay several star players big contracts.

The Chiefs had already picked up their fifth-year option in April on Mahomes, who had been due to make $825,000 on the final year of his rookie contract this season, to keep him around at least through 2021.

General manager Brett Veach said this deal has been a priority for quite a while.

"His abilities are so rare, and to couple that with an incredible personality is outstanding," Veach said of Mahomes.

"We're going to continue to do everything we can to surround him with talent, and this deal provides us more flexibility to do that. He's obviously an integral part to our success and we're thrilled he's going to be the quarterback of the Kansas City Chiefs for a long time."

Associated Press