Madonna's revamped Sticky and Sweet tour kicked off in London in July
Pop star Madonna made an emotional tribute to her fans after they delayed her Polish concert by singing Happy Birthday to her.
Gig-goers sang the song to her in both English and Polish at the start of the concert in Warsaw.
Madonna told her audience: "You changed my life."
Fans were slightly premature in their congratulations - the singer turned 51 on Sunday, a few hours after the Saturday night concert.
They also sang a traditional Polish birthday song, titled May You Live A Hundred Years, with video footage of the celebrations
posted on YouTube
The singer's voice wavered after the crowd finally quietened down to allow her to speak.
"Every time I do a show, and every time I look into your eyes and every time I see your smiles, you changed my life," she said in response.
"It's amazing that I've been able to do what I do for so many years, thank God, I love my job, I love being able to be here with you tonight.
"This is the best birthday present ever, so thank you," she added.
But it was not all plain sailing for the pop star - the concert fell on a Roman Catholic holiday celebrating the heavenly assumption of the Virgin Mary, which angered some Catholics.
Several people held up protest banners outside the concert venue.
Madonna's Sticky and Sweet tour was marred by the death of two stage technicians in France last month.
Charles Prow, from Headingley in Leeds, and French worker Charles Criscenzo, died after a partially-built roof fell in on Marseille's Velodrome stadium, bringing down a crane.
Eight other people were seriously hurt and more than 30 people suffered minor injuries and shock.
Madonna said she was "devastated" and visited the family of Mr Criscenzo and some of the injured workers.