In defense of Rufus Wainwright, a Canadian-American who sang the National Anthem at Dodger Stadium prior to Game 5 of the World Series, mistakes happen.
It can be intimidating to sing in front of 40,000+ fans. Many American fans may not have noticed Wainwright's clerical error.
A correct performance of the Canadian anthem on baseball's grandest stage is expected. Wainwright likely knows the words, as he volunteered to sing.
Mistakes happen.
Author's summary: Rufus Wainwright faced challenges singing O Canada.