UPDATE — I’ll Have Another will not lead the post parade for the Belmont Stakes as originally planned. Instead, the NYRA will hold a retirement ceremony for the Kentucky Derby and Preakness winner after the running of the Woodford Reserve Manhattan so fans can see him and pay tribute.

2012 Triple Crown hopeful I’ll Have Another retired. Will not run in Belmont Stakes due to injured tendon. CNN image.
JOE DRAPE, writing for The Rail / New York Times reports:
I’ll Have Another, the Kentucky Derby and Preakness Stakes winner who was aiming to become the 12th horse to win the Triple Crown, was scratched Friday from Saturday’s Belmont Stakes and later retired from racing because of a leg injury.
The 3-year-old colt, who had been a long-shot winner of the Derby and an impressive winner three weeks ago in the Preakness, has tendinitis in his left front leg, his trainer, Doug O’Neill, said.

Trainer Doug O’Neill at a news conference Friday to announce I’ll Have Another’s retirement. Chang W. Lee/The New York Times.
Although the gutsy 3-year old Chestnut I’ll Have Another could fully expect to recover and race again, it was announced at the Friday news conference that he will be retired instead.
Later in the same article Drape states:
O’Neill has insisted he is a clean trainer. He said he welcomed the intense monitoring. But almost inevitably, as soon as word of I’ll Have Another’s injury surfaced online, the wisecracks began, implying there might be an underlying or hidden drug issue involved.
I’ll Have Another will reportedly lead the Belmont Stakes parade. This idea began drawing criticism almost immediately on Twitter, where the news I’ll Have Another had been scratched was reported prior to the press conference formally announcing it. As a horse doctor tweeted: “Would you walk a half mile with baggage after spraining your ankle just for the cheers?”