The FCB supremo was thoroughly impressed with the Champions League titleholders' outing at the Etihad Stadium, believing it set a new standard of footballing excellence
The German giants recorded a 3-1 win over Manuel Pellegrini's men in this week's Champions League encounter at the Etihad and proved particularly impressive in the opening 45 minutes, as the expensively-assembled home side were pinned back in their own half.
Franck Ribery handed FCB a 1-0 lead at half-time, before Thomas Muller and Arjen Robben finished the job after the interval, and Rummenigge was astounded by the quality of the visitors' display.
"The first half of the game against Ciy was the best performance I have ever seen," the legendary striker told Bild.
"What our team showed in the first 80 minutes of the game was absolutely extraordinary."
Bayern top Group D of the Champions League with six points from two games, holding a three-point lead over City and CSKA Moscow.