Manager Roberto Mancini branded Balotelli "stupid" for the dismissal, for planting his studs into the chest and thigh of Dynamo defender Goran Popov.
Mancini felt the 36th-minute dismissal cost his side their chance of reaching the last eight and Balotelli has expressed his regret. "I am very sorry to my team-mates in particular that I got sent off so early in such an important game," said Balotelli.
It was the latest in a long line of controversies affecting the 20-year-old, who has mixed undoubted talent with an unerring ability to attract trouble since his summer arrival from Inter Milan.
In the past, Mancini has accused Balotelli of not listening to him and he has now claimed that the Italy forward may be axed for Sunday's crucial Premier League trip to Chelsea.
However, the Blues have confirmed Balotelli will be available for the Stamford Bridge encounter as the forward tried to explain what went wrong.
"I was trying my best for the team as I always do," he said. "The ball was in the air and I went for it with my foot high.
"I never tried to make contact with Popov and I certainly didn't want to hurt him. In retrospect, however, the tackle was poor.
"It was not a good way to repay the manager who has shown so much faith in me or the owners and fans who have made me so welcome since I arrived from Italy. I hope they forgive me and see that I want success with Manchester City."