Australia's injury-plagued paceman Ryan Harris announced his immediate retirement from all forms of cricket on Saturday, dealing a major setback to his team's defence of the Ashes starting in England next week. The 35-year-old Queenslander withdrew from Australia's ongoing warm-up match against Essex and walked away from the sport less than a week before the first of five tests against England starts at Cardiff on Wednesday. Cricket Australia announced that Pat Cummins would replace Harris in the Ashes squad. The Sydney test against India in January was Harris's last international match. Harris, who made his Test debut in 2010, took 113 wickets in 27 Test matches and 44 in 21 One-day Internationals.