Title: John O'Brien (Louth footballer)
Content:  John O'Brien (born 12 October 1985) is a current Gaelic player for Louth and Seán O'Mahony's.
Title: John O'Brien (soccer)
Content:  John Patrick O'Brien (born August 29, 1977) is an American former soccer player. After retiring, he pursued a career in psychology. O'Brien was one of the first Americans to earn a starting spot with a major European team, with Ajax Amsterdam in the late 1990s. At the peak of his career, United States national teammate Landon Donovan called O'Brien the "best soccer player in the USA."
Title: John O'Brien (Dublin footballer)
Content:  John O'Brien is a Gaelic footballer who played for the Round Towers club and at senior level for the Dublin county team. He made his debut in the 2008 O'Byrne Cup against Wicklow. O'Brien made his NFL debut for Dublin against Westmeath in the first round. He was on Dublin's winning team for the 2008 O'Byrne Cup winning team which defeated Longford in the final.
Title: John O'Brien (hurler)
Content:  John O'Brien (born 3 January 1982) is an Irish hurler who played as a centre-forward for the Tipperary senior team. Born in Toomevara, County Tipperary, O'Brien first arrived on the inter-county scene at the age of seventeen when he first linked up with the Tipperary minor team, before later joining the under-21 side. He made his senior debut during the 2001 league. O'Brien went on to enjoy a lengthy career, and won two All-Ireland medals, five Munster medals and one National Hurling League medals. He was an All-Ireland runner-up on three occasions. At club level O'Brien is a two-time Munster medallist with Toomevara. In addition to this he has also won seven championship medals and three county final Man of the Match awards. His brother, Paddy O'Brien, is also an All-Ireland medallist with Tipperary. Throughout his career O'Brien made 36 championship appearances. He announced his retirement from inter-county hurling on 26 November 2014.
Title: John O'Brien (water polo)
Content:  John O'Brien (8 October 1931 &ndash; 13 May 2020) was an Australian water polo player. He competed at the 1956 Summer Olympics and the 1960 Summer Olympics. In 2010, he was inducted into the Water Polo Australia Hall of Fame.
Title: John O'Brien (Louth footballer)
Content:  O'Brien made his senior debut in 2006 in the O'Byrne Cup against DIT and has been a permanent member of the Wee County since then. He is probably the best Right half backs for Louth and was part of the team who almost won the county's first Leinster title in over 53 years but was snatched controversially by neighbours Meath after ref Martin Sludden awarded a goal which proved to be a square ball and was thrown over the line. In early 2011 O'Brien announced his plans to emigrate to Australia in search for work alongside his team mates Michael Fanning and midfielder Brian White.
Title: John O'Brien (rower)
Content:  John O'Brien (1 June 1927 – 25 February 1995) was a New Zealand representative rower. At the 1950 British Empire Games he won the gold medal as part of the men's coxed four. At the 1952 Summer Olympics he competed as part of the coxed four again, but the crew did not make the final.
Title: John O'Brien (hurler)
Content:  inter-county hurling on 26 November 2014. In a released statement he said "I wish to announce my retirement from the Tipperary Hurling team. It has been an honour to have represented my county at senior level since my debut in 2001. I would like to thank everyone who has supported me and made it possible for me to play, most importantly my family and friends, my club Toomevara, the management and backroom teams throughout those years which are too many to mention and also the Tipperary public. I have made many great friends over those years and I would like to wish the current panel and management team the very best of luck."
Title: John O'Brien (basketball, born 1888)
Content:  John J. O'Brien (born November 4, 1888 – December 9, 1967) was an American basketball referee and administrator. Born in Brooklyn, New York, he was involved in organizing several early professional basketball leagues. In 1925, he founded Metropolitan Basketball League, which featured Original Celtics. From 1928 to 1953 he was an executive with American Basketball League, serving as president and, later, as chairman of the board. He was enshrined into the Basketball Hall of Fame as a contributor in 1961.
Title: John O'Brien (soccer)
Content:  O’ Brien lives with his wife and son near Boulder, Colorado. After retiring from football O’Brien returned to college and completed a doctorate in clinical psychology from the California School of professional Psychology in San Francisco. Dr O’Brien works with athletes around their mental health.

Question: What sport does John O'Brien play?
Answer: association football.
football.
soccer.