The National Football League (NFL) Network has revealed that Rees-Zammit, who played for English Premiership club Gloucester from 2018 until this year, has secured a three-year deal with the Kansas City Chiefs, with a signing bonus and a part of the contract guaranteed. 

The Chiefs announced on X that "Rees-Lightning has arrived," accompanied by a lightning bolt emoji and a snapshot of the 23-year-old Welsh athlete representing his country type above "Welcome to Chiefs Kingdom."

"Hi Chiefs Kingdom. Louis Rees-Zammit here. Just signed. Can't wait to go and see you all at Arrowhead (Stadium)," the player said in a video clip posted on X. "From the United Kingdom to Chiefs Kingdom," the Chiefs posted, adding the signing photos.

Rees-Zammit's dream of joining the NFL began in January, when he left rugby union to explore his options for an NFL career. Since then, he has joined the NFL's International Player Pathway Programme, which was established in 2017 to help international athletes make the transition to American football.

Last week, Rees-Zammit impressed scouts with a 4.44-second 40-yard dash, placing him fifth among tailbacks at this year's NFL Scouting Combine. He visited the New York Jets, Cleveland Browns, Denver Broncos, and the Chiefs, his new home in the NFL. 

He's the 37th player from the Global Talent Programme to sign with an NFL team and is aiming to become the sixth player to make an active roster. NFL teams have a training camp roster exemption for international players, with one global practice squad spot available this year for athletes like Rees-Zammit.

NFL teams can promote international players from the practice squad up to three times during the season. If Rees-Zammit's trip to the NFL is not successful, he will be welcomed back into the Welsh rugby.

Rees-Zammit, who has been touted for a number of roles including rusher and wide receiver, could earn a place on the main roster based on his performances in the Chiefs' training camp and pre-season games. However, only five players made the cut: Jordan Mailata, Efe Obada, Jakob Johnson, David Bada and Sammis Reyes.

NFL prospect Rees-Zammit could benefit from recent rule changes approved by NFL club owners this week, particularly regarding kick-offs. The new rugby-style format allows for blockers on kick returns, which could help his performance.