Sylvester Stallone has proved he's still a movie heavyweight by battling to the top of the UK box office with fighting film ROCKY BALBOA. The sixth installment of the Rocky series left the competition bruised by raking in GBP3.6 million ($7.2 million) since its Friday (19JAN07) release. THE PURSUIT OF HAPPYNESS, which features the Oscar-nominated Will Smith, and Ben Stiller comedy NIGHT AT THE MUSEUM were pushed into second and third place, taking GBP1.7 million ($3.3 million) and GBP1.4 million ($2.8 million) respectively. THE LAST KING OF SCOTLAND sits in fourth place, while Casino Royale remains in the box office top ten, with GBP54 million (GBP105 million) in box office takings since its release last year (06).