Group One-winning sprinter The Quarterback has been retired after two disappointing runs this campaign.

The winner of the 2016 Newmarket Handicap, The Quarterback finished last at his past two starts on the straight course at Flemington and both times was found to have exercise-induced pulmonary haemorrhage.

Trainer Robbie Griffiths said he and the owners had decided it was in the best interests of the horse to call time on his racing career.

“It is not only with great sadness but also delight for what lies ahead for Griffiths Racing’s sensational sprinter The Quarterback,” Griffiths said on his website.

“Griffiths Racing together with the owners and connections have reached the decision that has seen our champion and headline horse retired.

He has brought great joy, anticipation and success to his owners not too mention realising my greatest wish as a trainer in winning my first Group 1, The Newmarket Hcp.

“We are delighted to announce that after a lengthy spell he will be gifted to his attendant Leanne, who will ensure he will have a lovely life as a show horse.”

The Quarterback retired with nine wins from 34 starts and prize money in excess of $1.5 million.

Credit: AAP