The explanation was a teleprompter malfunction.
In mid-anthem, Amber Iman, a Broadway singer cast in the national tour of Hamilton, sang, “O Canada, we sing our hearts for thee.” The line that ends the song is “O Canada, we stand on guard for thee.”
Oh well.
Twitter trolls went after Iman in the aftermath and the singer responded...
“I learned the melody while in eight hour ‘Hamilton’ rehearsals. The prompter failed, I did my best, while u watched from your couch.”
Later, she noted, the Nets had apologized profusely to her for the malfunction.