Pop star Rihanna postponed Sunday's planned concert at TD Garden in Boston because of laryngitis, reports Newsday's Frank Lovece. Concert organizer Live Nation said in a statement, "Unfortunately, following her sold-out concert on Friday [in Buffalo], Rihanna has contracted laryngitis and per doctor's instruction is unable to perform this evening." Rihanna, 25, later tweeted, "Boston, this is the hardest thing for me to deal with! I feel like we've been waiting on this day forever, and I'm hurt that I let you down. I hate disappointing people that never ever let me down!! I'm so embarrassed about this! Thank you for your prayers and well wishes!" Live Nation said the show would be rescheduled. Rihanna is due to play Baltimore Tuesday.