Roma president James Pallotta agreed to pay a fine and apologized to Mayor Virginia Raggi on Wednesday after jumping into a downtown fountain to celebrate the win over Barcelona.

Surrounded by a crowd of flag-waving Roma fans, Pallotta performed a backward somersault in his dress shirt and pants into a fountain in the Piazza del Popolo.

Pallotta was ecstatic after Roma surprised Barcelona with a 3-0 win Tuesday to overturn a three-goal first-leg deficit in the Champions League quarterfinals.

Pallotta, a Boston executive who was part of the four-man American team that purchased Roma in 2011, is also a minority owner of the Boston Celtics.

City ordinances call for a 500 euro ($600) fine for wading into historic fountains.

"We spoke and he apologized," Raggi said. "He did it in a moment of excitement but he realizes the importance of the example he needs to provide. And clearly he'll pay the fine."

Pallotta was to see Raggi later Wednesday for a previously scheduled meeting.

Roma is still seeking final approval to start construction on a new stadium inspired by the Colosseum.