Madonna onstage for her Sticky and Sweet tour
12/03/2008 AT 12:20 PM EST
Scratch Argentina from Madonna
's date book on Wednesday.
The pop star, 50, has postponed the first of her four Buenos Aires concerts on her "Sticky & Sweet" tour. She will perform as scheduled on Thursday, Saturday and Sunday, reps for River Plate Stadium tell the Associated Press at the request of the Time 4 Fun production company – which would not comment further.
Local press in the city – backdrop of Madonna's 1996 movie musical Evita
– report a delay in the arrival of the singer's sound equipment. Her show is now set to go on come Monday.
Last week, say reports, Madonna was spotted in Mexico City
, where New York Yankee Alex Rodriguez was also seen.
– Stephen M. Silverman