1886 in sports describes the year's events in world sport.
- Arsenal FC founded as Dial Square FC by munitions workers from the Royal Arsenal at Woolwich in southeast London. Dial Square is the name of one of their workshops. At the end of the year, the players hold a pub meeting and change the club's name to Royal Arsenal. Five years later, the name is changed to Woolwich Arsenal. The club's present name will be adopted in 1914 after the move to Islington.
- 13 March — Tinsley Lindley scores in the first of his record 9 consecutive England games
- 10 May — The Football Association approves a proposal made by N. Lane Jackson, an Old Corinthian, that players be given a cap for every international match in which they take part.
- FA Cup final – Blackburn Rovers 2–0 West Bromwich Albion at The Oval; replay after 0–0 draw at The Oval. This is Blackburn's third successive victory and the final is the first to feature two extant members of The Football League.
- December 11 – Dial Square F.C., later to become Arsenal FC (see above)), play their first match, a 6–0 win over the Eastern Wanderers.
- 20 March — John Lambie becomes the youngest Scotland player and captain, aged 17 years and 92 days.
- May 17— Motherwell Football Club is formed.
- Scottish Cup final – Queen's Park 3–1 Renton
- Grasshopper Club Zürich founded.
- The Sporting News established in St. Louis. It becomes the dominant American publication covering baseball, so much so that it acquires the nickname "The Bible of Baseball".
- The inaugural World Lightweight Champion is Jack McAuliffe, generally recognised following his 21st-round knockout of Billy Frazier at Boston. Lightweights weigh 130 to 135 pounds. McAuliffe will hold the title until he retires undefeated in 1893.
- Jack Nonpareil Dempsey retains the World Middleweight Championship when he knocks out George LaBlanche in 13 rounds at Larchmont, NY.
- John L. Sullivan knocks out Paddy Ryan in the third round at San Francisco. Sullivan retains the World Heavyweight Championship.
Lineal world champions
- World Heavyweight Championship – John L. Sullivan
- World Middleweight Championship – Jack Nonpareil Dempsey
- World Lightweight Championship – Jack McAuliffe
- Somerset does not play against any other first-class counties and drops out of the County Championship until 1891.
- Hampshire ceases to be a first-class county after years of difficult circumstances and poor results. They do play matches against Surrey and Sussex in 1886 but these matches are not recognised as first-class. Hampshire will not recover first-class status until the beginning of the 1895 season when they will be readmitted to the County Championship.
- Champion County – Nottinghamshire (fourth consecutive season)
- Most runs – W. G. Grace 1,846 @ 35.50 (HS 170)
- Most wickets – George Lohmann 160 @ 15.15 (BB 8–43)
- 18 January — modern field hockey is born with the formation of the Hockey Association in England, which codifies the sport's rules
- Wexford GAA becomes the first of the 32 GAA county boards
- Grand National – Old Joe
- 1,000 Guineas Stakes – Miss Jummy
- 2,000 Guineas Stakes – Ormonde
- The Derby – Ormonde
- The Oaks – Miss Jummy
- St. Leger Stakes – Ormonde
- Melbourne Cup – Arsenal
- Queen's Plate – Wild Rose
- 8 December — world's first championship ice hockey league, the Amateur Hockey Association of Canada (AHAC) is formed at a meeting in Montreal
The Boat Race
Home Nations Championship
- Wimbledon Men's Singles Championship – William Renshaw (GB) defeats Herbert Lawford (GB) 6–0 5–7 6–3 6–4
- Wimbledon Women's Singles Championship – Blanche Bingley (GB) defeats Maud Watson (GB) 6–3 6–3
- American Men's Singles Championship – Richard D. Sears (USA) defeats R. Livingston Beeckman (USA) 4–6 6–1 6–3 6–4
- The 10th pre-open era Men's Tennis tour gets underway 85 tournaments are staged this year the tour runs from 24 April to 12 November 1886.
- The New York Yacht Club retains the America's Cup as Mayflower defeats British challenger Galatea, of the Royal Northern Yacht Club, 2 races to 0
- "Scottish Cup Past Winners | Scottish Cup | Scottish FA". www.scottishfa.co.uk. Retrieved 5 February 2021.
- Cyber Boxing Zone – Jack McAuliffe. Retrieved on 13 November 2009.
- Cyber Boxing Zone – Jack Nonpareil Dempsey. Retrieved on 13 November 2009.
- Cyber Boxing Zone – John L Sullivan. Retrieved on 13 November 2009.
- "Cyber Boxing Zone". Archived from the original on 2009-06-14. Retrieved 2009-06-17.
- A semi-official seasonal title proclaimed by media consensus prior to December 1889 when the official County Championship is constituted.
- "Epsom Derby | History, Winners, & Facts | Britannica". www.britannica.com. Retrieved 29 December 2021.