He never appeared on the show but....
Well, Just who the heck is Howard Cosell anyway?

Howard Cosell
 Sportscaster

Birthday: March 25, 1920
Birth Place: Winston-Salem, North Carolina, USA
Birth Name: Howard Norman Cosell
Date of death: April 23, 1995
Cause of death: Heart Embolism (New York, New York, USA)

One of the most controversial personalities in the history of American broadcasting, Cosell was a World War II army major and a New York City lawyer before he joined the American Broadcasting Company as a radio sports reporter in 1956. He attracted national attention for the first time in 1959 with his commentaries on world heavyweight fights.
His interviews with Cassius Clay created interest and amusement. Much of Cosell's early television work revolved around the heavyweight titleholder. He was the first person to publicly use the champion's Black Muslim name, and in 1967 he vigorously defended Muhammad Ali against charges of draft evasion.
In the emotion-charged era of the Vietnam War and civil rights agitation, Cosell's actions evoked a storm of protest and expressions of anti-Semitism. Many demanded he be fired but he was not.
In 1970 he became the star of the reporting team of "Monday Night Football." The great success of the weekday telecast of the National Football League game was attributed to Cosell. Exciting game or not, people stayed tuned just to hear what Cosell had to say about the contest, the players, the coaches, the host city, and just about anything else.
The product of a non-religious family, Cosell never had a bar mitzvah and had never involved himself in the life of the Jewish community. That all changed after his 1972 Olympic Games experience. The murder of Israeli athletes in Munich, West Germany, made him feel "intensely Jewish," and he joined the American Friends of the Hebrew University, which built the Howard Cosell Center for Physical Education in Jerusalem.
He quit "Monday Night Football" after the 1983 season and retired from A.B.C. Television in 1985. The following year he became a sports columnist for the New York Daily News.
[Jesse Harold Silver]
Content from: www.jewishsports.com

Starring Roles:
Battle of the Network Stars (1976) - Host
Saturday Night Live with Howard Cosell (1975) - Host
Monday Night Football (1970) - Commentator [1970-ca. 1984]
ABC's Wide World of Sports (1961) - Commentator (1964-1985)

Guest Roles on:
SportsCentury - Himself [ABC Sports footage] - Pete Rozelle (2001)
SportsCentury - Himself (archive footage) - Joe Namath (2001)
Lost Treasures of NFL Films - Himself [1973 footage] - Network Stars of the 70's (2000)
SportsCentury - Himself [ABC Sports footage] - Muhammad Ali (2000)
Lost Treasures of NFL Films - Himself [1969 footage] - The End of an Era (2000)
The Tonight Show Starring Johnny Carson - Guest - 880120 (1988)
Late Night With David Letterman - Guest - Show #0956 (1987)
Late Night With David Letterman - Guest - 861103 (1986)
The Tonight Show Starring Johnny Carson - Guest - 860911 (1986)
Tall Tales and Legends - announcer - Casey at Bat (1986)
The Tonight Show Starring Johnny Carson - Guest - 851204 (1985)
Saturday Night Live - Himself - Howard Cosell/Greg Kihn (1985)
Battle of the Network Stars - Host - Special #17 (1984)
Battle of the Network Stars - Host - Special #16 (1984)
Battle of the Network Stars - Host - Special #15 (1983)
Battle of the Network Stars - Host - Special #14 (1983)
Battle of the Network Stars - Host - Special #13 (1982)
Battle of the Network Stars - Host - Special #12 (1982)
Battle of the Network Stars - Host - Special #11 (1981)
Battle of the Network Stars - Host - Special #10 (1981)
Battle of the Network Stars - Host - Special #9 (1980)
Battle of the Network Stars - Host - Special #8 (1980)
Battle of the Network Stars - Host - Special #7 (1979)
Battle of the Network Stars - Host - Special #6 (1979)
Battle of the Network Stars - Host - Special #5 (1978)
Battle of the Network Stars - Host - Special #4 (1978)
Battle of the Network Stars - Host - Special #3 (1977)
Battle of the Network Stars - Host - Special #2 (1977)
Battle of the Network Stars - Host - Special #1 (1976)
The Odd Couple - Himself - Your Mother Wears Army Boots (1975)
The Dean Martin Show - Himself - Episode #223 (1973)
The Dean Martin Show - Himself - Episode #221 (1973)
The Dean Martin Show - Himself - Episode #217 (1973)
Rowan & Martin's Laugh-In - Cameo Appearance - Episode #130 (1972)
The Odd Couple - Himself - Big Mouth (1972)
The Tonight Show Starring Johnny Carson - Guest - 720626 (1972)
The Tonight Show Starring Johnny Carson - Guest - 720420 (1972)
The Tonight Show Starring Johnny Carson - Guest - 720403 (1972)
The Tonight Show Starring Johnny Carson - Guest - 720308 (1972)
The Tonight Show Starring Johnny Carson - Guest - 720131 (1972)
The Partridge Family - Himself - Whatever Happened to Moby Dick? (1971)
Nanny and the Professor - Miles Taylor - Sunday's Hero (1971)
The Joe Namath Show - Himself - Jerry Kramer and Howard Cosell (1969)
Dean Martin Celebrity Roast - Guest
The Sonny & Cher Comedy Hour - Guest Star - Show 44 - Season Premiere

Movie/Mini-Series/Special Roles
When We Were Kings (1996) - Himself (uncredited)
Sleeper (1973) - Himself (file footage)
The World's Greatest Athlete (1973) - Announcer
Bananas (1971) - Himself