Commanche Run got his first win twelve days later on 28 May at Doncaster Racecourse. Moving up in company, the colt ran third in the 1984 King Edward VII Stakes and the Princess of Wales's Stakes, then won his next two starts at Goodwood Racecourse, taking both the Gordon and the March Stakes. Under jockey Lester Piggott, Commanche Run went on to win three Group One races, capturing the Benson & Hedges Gold Cup, Irish Champion Stakes and the Classic St. Leger Stakes. Retired to stud duty at Coolmore Stud in Ireland, Commanche Run met with limited success. In 1999 he was
Gunner B offered at odds of 8/1 for the St Leger Stakes. He then produced a creditable effort in defeat in an on mile handicap at Beverley, finishing third under a weight of 141 pounds. When Gunner B contested the Gordon Stakes, a recognised St Leger trial at Goodwood however, he ran poorly and finished last of the six runners. Gunner B bypassed the St Leger, running instead in the Doonside Cup over eleven furlongs at Ayr Racecourse in which, ridden by Mercer, he was required to concede weight to older horses including Patch (Great Voltigeur Stakes), Rymer (Brigadier Gerard Stakes) and