Question: Rocky IV co-starred the actor who was involved in what other sport besides boxing?
Context: Rocky VI is a 1986 nine-minute black-and-white short parody of "Rocky IV" by Finnish director Aki Kaurismäki.  The film stars Antti Juhani "Silu" Seppälä (Leningrad Cowboys) as Rocky and Sakari Kuosmanen as Igor, his Soviet opponent.  In the film, the two boxers fight at Töölö Sports Hall in Helsinki.  The much bigger Igor quickly knocks out Rocky and wins the match. This is a list of characters from the "Rocky" film series, consisting of "Rocky" (1976), "Rocky II" (1979), "Rocky III" (1982), "Rocky IV" (1985), "Rocky V" (1990), "Rocky Balboa" (2006), and "Creed" (2015). Anthony "Tony" Burton (March 23, 1937 – February 25, 2016) was an American actor, boxer, and football player.  He was known for his role as Tony "Duke" Evers in the "Rocky" franchise.  He, Sylvester Stallone and Burt Young are the only actors who have appeared in every Rocky installment (not counting "Creed"). Rocky is a series of boxing films based on the eponymous, fictional character Rocky Balboa, played in each film by Sylvester Stallone.  The films by order of release date are: "Rocky" (1976), "Rocky II" (1979), "Rocky III" (1982), "Rocky IV" (1985), "Rocky V" (1990), "Rocky Balboa" (2006) and "Creed" (2015).  The film series has grossed more than $1.4 billion at the worldwide box office. Vincent Louis "Vince" DiCola (born November 1957) is an American composer, keyboardist and arranger.  He has composed scores for films such as "", "Staying Alive" and "Rocky IV" soundtracks.  DiCola also pioneered the use of sequencers on his soundtrack recording for "Rocky IV", one of the first to exploit the Fairlight CMI and Synclavier II's computer's sequencing capabilities. Anthony N. Villanueva (March 18, 1945 – May 13, 2014) was a boxer from the Philippines.  He competed in the featherweight (−57 kg) division at the 1964 Olympics and won a silver medal.  Shortly after the Olympics he turned professional, but retired after five bouts.  Besides boxing, Villanueva worked as an actor and boxing coach in the Philippines and as a security guard in the United States.  He died penniless and bedridden after suffering several strokes. Ivan Drago (Russian: Иван Драго ) is a fictional character in the 1985 film "Rocky IV", in which he is Rocky Balboa's rival and the main antagonist.  He is portrayed by Dolph Lundgren.  Like the Clubber Lang character from "Rocky III", the character and his catchphrases have gone on to inspire multiple mentions in popular culture, including in the "Family Guy" episodes "Brian Goes Back to College" and "Something, Something, Something, Dark Side", the "Chuck" episodes "Chuck Versus the Final Exam" and "Chuck Versus the Anniversary", and the film "Disaster Movie".  A poll of former heavyweight champions and prominent boxing writers ranked Drago as the third best fighter in the "Rocky" film series. The 72 stone steps before the entrance of the Philadelphia Museum of Art, in Philadelphia, Pennsylvania, have become known as the "Rocky Steps" as a result of their appearance in the triple-Oscar-winning film "Rocky" and all of the series' sequels except for "Rocky IV", in which the eponymous character runs up the steps to the song "Gonna Fly Now".  Tourists often mimic Rocky's famous climb, a metaphor for an underdog or an everyman rising to a challenge.  A bronze "Rocky" statue was briefly situated at the top of the steps for the filming of "Rocky III".  This statue, now located at the bottom right of the steps, is a popular photo opportunity for visitors.  The top of the steps offers a commanding view of Eakins Oval, the Benjamin Franklin Parkway, and Philadelphia City Hall. "Man Against the World" is a song by American rock band Survivor.  It was the fourth track and the third single released from their 1986 album "When Seconds Count".  The song was originally to be included on the soundtrack to the 1985 film "Rocky IV" but was cut.  The song did appear as a bonus track on the 2006 reissue of the "Rocky IV soundtrack" album, along with Survivor's two other Rocky-related singles - the #1 hit "Eye of the Tiger" (the smash hit from "Rocky III") and "Burning Heart," which was the song ultimately chosen for the "Rocky IV" soundtrack and peaked at #2. Rocky IV is a 1985 American sports drama film written, directed by, and starring Sylvester Stallone.  The film co-stars Dolph Lundgren, Burt Young, Talia Shire, Carl Weathers, Tony Burton, Brigitte Nielsen, and Michael Pataki.  "Rocky IV" remained the highest grossing sports movie for 24 years before it was overtaken by "The Blind Side".  It is the fourth and most financially successful entry in the "Rocky" film series.
Answer: football