The Portugal winger accepted the responsibility in the Champions League clash with Galatasaray at Old Trafford, and promptly became the third United player to fail, following Robin van Persie and Javier Hernandez.
"I took a bad penalty, Van Persie took a bad one," admitted Nani.
"I am sure next time, no matter who takes it, we will score. I would take one again. If the manager agrees I would do it - and score."
The manager will not agree though. Indeed, Sir Alex Ferguson had no idea why Nani was taking the kick in the first place.
"I think he just ran and grabbed the ball," said the United boss.
"I thought Robin should have taken it, to be honest with you.
"I think we will have to decide before the game. That was my fault, I should have done that."