Question: In which sport do Zimbabwean Byron Black and United States coach Rick Leach both hold professional status? 

Context paragraphs:
Byron Black: Byron Black (born 6 October 1969 in Harare, Zimbabwe) is a former touring professional tennis and Davis Cup player for Zimbabwe.

1969 Navy Midshipmen football team: The 1969 Navy Midshipmen football team represented the United States Naval Academy (USNA) during the 1969 college football season.  Navy competed as an independent with no conference affiliation.  The team was led by first-year head coach Rick Forzano.

1988 US Open – Men's Doubles: The Men's Doubles tournament at the 1988 US Open was held from August 29 to September 11, 1988, on the outdoor hard courts at the USTA National Tennis Center in New York City, United States.  Sergio Casal and Emilio Sánchez won the title, defeating Rick Leach and Jim Pugh by walkover in the final.

History of the St. Louis Cardinals (1875–1919): The St. Louis Cardinals, a professional baseball franchise based in St. Louis, Missouri, compete in the National League (NL) of Major League Baseball (MLB).  As the game of baseball garnered interest in the United States in the 19th century, professional baseball in St. Louis became rooted chiefly in one disestablished Major League club – named the Brown Stockings, the same as the Cardinals' earliest name – which is loosely connected, but does not fall within the scope of, today's Cardinals.  The Brown Stockings became St. Louis' first fully professional baseball club when they gained accession in the National Association (NA) in 1875.  However, the NA folded after that season.  That winter, with five other former NA teams, St. Louis established a new, eight-team league called the National League (NL) and began play the next season.  Despite early success, Brown Stocking players were found to be connected to game fixing scandals, which forced bankruptcy and the club's expulsion from the NL.  This scandal also abrogated their professional status but some members maintained play as a semi-professional team, primarily operated by outfielder Ned Cuthbert, until 1881.

1993 Volvo International – Doubles: The 1993 Volvo International was a tennis tournament played on outdoor hard courts at the Cullman-Heyman Tennis Center in New Haven, Connecticut, United States and was part of the Championship Series of the 1993 ATP Tour.  The tournament ran from August 16 through August 23, 1993.  Kelly Jones and Rick Leach were the defending champions but only Jones competed that year with Paul Annacone.  Annacone and Jones lost in the semifinals to Cyril Suk and Daniel Vacek.  Suk and Vacek won in the final 7–5, 6–4 against Steve DeVries and David Macpherson.

Rick Leach: Rick Leach (born December 28, 1964) is a former professional tennis player and a coach from the United States.  A doubles specialist, he won five Grand Slam men's doubles titles (three Australian Open, one Wimbledon, one US Open), and four Grand Slam mixed doubles titles (two Australian Open, one Wimbledon, one US Open).  Leach reached the World No. 1 doubles ranking in 1990.

1993 US Open – Men's Doubles: The Men's Doubles tournament at the 1993 US Open was held from August 30 to September 12, 1993, on the outdoor hard courts at the USTA National Tennis Center in New York City, United States.  Ken Flach and Rick Leach won the title, defeating Karel Nováček and Martin Damm in the final.

Kenny Arena: Kenneth Scott "Kenny" Arena (born February 6, 1981) is an American former soccer defender who is currently an assistant coach for the United States.  Arena is the son of former long-time Major League Soccer and current United States coach Bruce Arena.

1992 US Open – Men's Doubles: The Men's Doubles tournament at the 1992 US Open was held between August 31 and September 13, 1992, on the outdoor hard courts at the USTA National Tennis Center in New York City, United States.  Jim Grabb and Richey Reneberg won the title, defeating Kelly Jones and Rick Leach in the final.

Ellis Ferreira: Ellis Ferreira (born 19 February 1970 in Pretoria, South Africa) is a former professional male tennis player from South Africa.  He played collegiately at the University of Alabama, earning all-SEC and all-American honors.  He won 2 Grand Slam doubles titles, the Men's title at the 2000 Australian Open with Rick Leach and the mixed doubles at the Australian Open with Corina Morariu in 2001.  Ferreira was named the Senior Assistant Men's and Women's Tennis Head Coach at Washington College in Chestertown, Maryland, in July 2007.  Ferreira is now the co-owner of the Eagleton/ Ferreira Tennis Academy on Longboat Key in Florida (www.eftennis.com).

Supporting paragraphs: Rick Leach Byron Black
Answer: tennis