The CFL also effectively barred Manziel from joining any other team in the league.
According to Shefter, Manziel would have been allocated to San Antonio, but the Commanders waived his rights, so the controversial quarterback will go through the league's waiver system.
Montreal Alouettes quarterback Johnny Manziel (2) throws a pass against the Hamilton Tiger-Cats during the first half of a Canadian Football League game Friday, Aug. 3, 2018, in Montreal.
The AAF signed Manziel to a player contract, announcing the news during the broadcast of Saturday's Arizona Hotshots-Orlando Apollos game.
Teams with the worst records in the league will get the chance to pick him up, according to ESPN.
Nadal WD's before Federer clash with knee injury
What can I say? "I will try my best to recover - these are the matches I want to play", the 32-year-old said, BBC Sport reported. The Nadal-Federer matchup would have been the 39th meeting in their careers and the first in 16 months.
The eight-team AAF is midway through its inaugural season this spring.
The 2012 Heisman Trophy victor will go through the AAF waiver system, per Schefter, after the San Antonio Commanders renounced his college allocation rights.
The Express have struggled to find a successful quarterback so far this year, which could provide Manziel a quick opportunity to take the field.
Johnny Manziel has officially entered the AAF, having signed the standard player agreement on Saturday. He's their second quarterback this season, after the team started with Christian Hackenberg but later benched the former Penn State quarterback. Brandon Silvers filled in for Mettenberger after he exited with an ankle injury in the 22-9 loss to the Stallions. He washed out of the National Football League less than two years after the Cleveland Browns selected him in the first round, making just eight starts and throwing as many interceptions as touchdowns (seven).
Manziel, 26, was the first freshman to win the Heisman Trophy.