The NFL Referees Association responded Thursday to criticism from the league that two recent calls made by officials on the field were incorrect.

The union called out the NFL for its inconsistencies in grading calls, saying the league has “caused confusion for NFL officials as to what the league does and doesn’t want called.”

The calls in question involved Kansas City Chiefs safety Husain Abdullah celebrating a interception return for a touchdown on Monday night and a hit by Washington’s Chris Baker on Philadelphia Eagles quarterback Nick Foles on Sept. 21.

Abdullah was flagged for a 15-yard penalty when he slid to the ground into the end zone to pray on his knees after his interception return against the New England Patriots. Baker was flagged and ejected for his hit on Foles. According to NFL rules, praying is exempted from the celebration flag, but sliding is not.

The union said both called were graded as correct, but the league later said publicly that the calls were not correct.

“In the last two weeks, two penalties that were called in games that drew national attention were publicly announced to be in error by the League office, however the Officiating Department later graded the calls as correct. This has caused confusion for NFL officials as to what the League does and doesn’t want called,” the Referees Association said in a statement.

The Referees Association said the league told the official who made the call on Baker

the day after that he ruled correctly. In Abdullah’s case, the flag was thrown because Abdullah slid on his knees in the end zone and not because he was praying.

“The player was flagged, correctly, for the slide on his knees in the end zone, not for going to the ground in a prayerful gesture,” former referee Scott Green in the Referees Association’s statement. “On-field officials are aware of the prayer provision and respect the right of players of all faiths to express themselves.”