DETROIT (CBS) — A year after former Detroit Tigers pitcher Armando Galarraga lost a perfect game after a missed call by umpire Jim Joyce, the two are forbidden from participating in games together.

On June 2, 2010, Galarraga pitched 8 2/3 perfect innings against the Cleveland Indians at Comerica Park, retiring 26 batters. But in the bottom of the ninth, first-base umpire Jim Joyce ruled that the Indians’ Jason Donald was safe on first base after hitting a ground ball.

The Tigers still won 3-0, but Galarraga’s near-perfect game ended up being a one-hit shutout.

Now, USAToday reports Joyce and Galarraga are forbidden from taking the field during the same game, but it’s not because of ongoing hostility.

The reason is that Galarraga and Joyce wrote a book together, titled Nobody’s Perfect: Two Men, One Call, and a Game for Baseball History. MLB tells USAToday that they are now barred from being involved in the same games so “there wasn’t any appearance of impropriety.”

Galarraga and Joyce’s book was released Thursday. Galarraga is now with the Arizona Diamondbacks.

The Tigers will face the White Sox at U.S. Cellular Field Friday evening.