Sunday, the Phillie Phanatic’s birthday will be celebrated at Citizens Bank Park. The Phillies revealed this morning that they will wear their batting practice caps that feature the Phanatic with their cream uniforms during their series finale with the Chicago White Sox.

There’s no indication that this is more than a one-time thing for the Phanatic’s birthday, though the Phanatic batting practice caps are pretty similar to the hats the Phillies typically wear with their cream uniforms. Perhaps it will become an annual tradition to wear the Phanatic caps on the mascot’s birthday, which is always celebrated on a Sunday in April.

The Phillies introduced their popular cream alternate uniforms in 2008, which are based off of the primary home uniforms that the Phillies wore from 1946-1949. They are worn for all home day games, except for Thursdays and Fridays.

You can learn more about the Phillies current uniform rotation below.