Tyson Smith, a Michigan State cornerback who started in four games in 2016 for the Spartans, tweeted Thursday that he had a stroke last year.
In the tweet, Smith said "doctors say I'm blessed to still be able to walk." Smith recorded 13 tackles and had four passes defended before missing the final three games of the 2016 season.
Smith did not appear in the team's spring game April 1, according to the Lansing State Journal.
The junior defensive back followed the initial tweet with a second tweet celebrating his birthday.
The Spartans were racked by injuries during their 2016 campaign and won just three games, finishing with their most losses since 1982.
Smith also appeared in seven games in 2015.