David Joseph Walsh (born 17 June 1955) is an Irish sports journalist, who is chief sports writer of the British newspaper The Sunday Times. He is a four-time Irish Sportswriter of the Year and a three-time UK Sportswriter of the Year. Walsh was the key journalist in uncovering the doping program by Lance Armstrong and the US Postal Service Cycling Team. Walsh was vindicated when Armstrong was stripped of all seven of his Tour titles, and banned from cycling for life, on 22 October 2012.
Walsh began his career as a cub reporter on the Leitrim Observer, where he worked his way up to become editor at 25. He left the paper to join the Dublin-based daily the Irish Press.
In 1984 he took a year out to cover cycling sport in Paris. Returning to his Dublin-based paper after that year he ultimately left in 1987 to work for the Sunday Tribune before moving onto the rival Sunday Independent four years later. Walsh joined The Sunday Times in Ireland in 1996 and began working on the story about doping in professional cycling shortly after moving to England in 1998.
Walsh was the ghost writer for cricketer Kevin Pietersen's autobiography, published in October 2014.
Referred to as the 'Little Troll' by Lance Armstrong, Walsh along with fellow Irishman and Sunday Times journalist Paul Kimmage, led the way in exposing the systematic doping rife within cycling, in particular the US Postal Team and its leader Lance Armstrong. Walsh revealed in the Sunday Times in 2001 after a two-year investigation that Armstrong was working with the controversial Italian doctor Michele Ferrari. Under the headline "Champ or Cheat?" The Sunday Times asked in 2001 why a clean rider would work with a dirty doctor.