Simplify the following text for a Grade 11 native English-speaking person.
Original: At end of the fifth overtime period , managers Conn Smythe of the Maple Leafs and Art Ross of the Bruins ask the president of the NHL , Frank Calder , to stop the game , and finish it later . Calder refused .
Simplified: After the end of the fifth overtime period , managers Conn Smythe of the Maple Leafs and Art Ross of the Bruins asked league president Frank Calder to suspend the game , but Calder refused .