In 1942 Kennefick made his senior championship debut in a Munster semi-final defeat of Limerick. He won his first Munster that year as Tipp were downed by 4–15 to 4–1 in the subsequent provincial decider. The All-Ireland final was a replay of the previous year with Dublin providing the opposition once again. The game was a close affair with just a point separating the sides at the three-quarter stage. In the end Cork won comfortably enough by 2–14 to 3–4 and Kennefick collected his first All-Ireland medal.