Watkins Glen International has released its 2018 racing lineup -- and IndyCar didn't make the cut.

After two years of partnership, the two decided to part ways for the upcoming season.

According to a statement tweeted by WGI, scheduling conflicts are to blame for the split. It says in part:

"This is a decision based purely on an inability to find a date that works for the fans, the series, and the track."

WGI says that they will remain in communication with IndyCar should a future partnership opportunity become available.