The shot would have had a photo finish only that Ranbir's blow landed on the wrong face! In an accidental miss he happened to hit Katrina. An unintentional blow from Ranbir left Katrina bleeding nose.
It is known from the sources, Ranbir immediately apologized to the actress, but she took no offence because she knew the blow was not intentional. However, delicate Katrina was hurt and had to be given first-aid on the sets.
Rajkumar Santoshi was so very worried that he called off shooting for the day. Even the next day, too, Santoshi did not shoot the film but used the free time to do some decoration on the sets.