Manziel issued a statement saying, "The Spring League has provided me with a great opportunity to play ball again, and ultimately, that is all I want to do."
"I miss the competition. I'd like to thank Brian Woods and The Spring League staff for this opportunity to play the game I love. I've made my share of mistakes, but I'm 25 years old and I know my best football is ahead of me."
The Spring League had previously made 2 conditions for Manziel to play -- nightly check-ins with a team staff member at 9:30 PM AND he must pass a USADA drug test on the first day of the league.
No word if those conditions still apply.
The League tells TMZ Sports, "We believe our platform is the ideal forum for Mr. Manziel to enact his NFL comeback."