A rep for Al Jarreau tells TMZ he was diagnosed with pneumonia before the concert, saying, "Mr. Jarreau believes that his illness and fatigue resulted from a very busy week on tour, which included 4 concerts in Austria. He will spend a short time recovering at home before resuming his normal work schedule.
Legendary singer Al Jarreau canceled a concert this evening in Escondido, CA ... TMZ has learned.
Jarreau was scheduled to perform at The Centre at Lexus Escondido, but the concert hall said Jarreau would not be performing because he was ill. A source close to the situation told TMZ he was taken to the hospital, but the concert hall would not confirm.
The entire concert was not canceled -- George Duke, who is also on the bill, will still perform.
Jarreau, who is 72, has won 6 Grammys ... including one as recent as 2007... and nominated for 12 more.