As Giggs accepts, Monday night marks a collision between the best two teams in the country, both of which thought they had the trophy won at some point over the past couple of months.
"We're the two best teams, there's no doubt about that," said Giggs.
"Whereas Tottenham and Chelsea have fallen by the wayside, we've carried on going.
"City were on fire pre-Christmas and really we were just trying to hang on, then we've come into form over the second half of the season.
"Now it's come down to this. We're neck and neck and it's about whoever puts in the performance."