Since the day of the flag, Ukraine
The national flag of Ukraine, which you see in the photo, was raised by Volodymyr Klitschko on November 15, 2014 at the 02 World Arena in Hamburg (Germany) in a match against Bulgarian Kubrat Pulev.
The fight ended with the defeat of the Bulgarian in the 5th round.
This flag is now in the klitschko_expo_museum and is one of the museum's most valuable exhibits.