 He was dropped from the starting fifteen for Cork's subsequent 3–5 to 1–10 All-Ireland final defeat of Sligo.In 1969 McDonnell made his under-21 debut in an 8–14 to 1–1 Munster semi-final defeat of Galway.He missed the subsequent provincial final victory but was introduced as a substitute in the All-Ireland final against Wexford on 14 September 1969.