Question: How many seasons did Walt Downing's coach at the University of Michigan spend as head coach?

Context paragraphs:
Fred Jackson (American football coach): Fred Jackson (born June 9, 1950) is an American football coach and former player.  He currently serves as the head football coach at Ypsilanti High School in Ypsilanti Township, Michigan.  He was previously the running backs coach at the University of Michigan.  In 2014, he was the longest tenured member of the Michigan Wolverines football coaching staff, having been with the program since 1992.  Jackson served on the staffs of Gary Moeller, Lloyd Carr, Rich Rodriguez, and Brady Hoke.  In addition to coaching running backs, Jackson served as Michigan's offensive coordinator (1995–1996), assistant head coach (1997–2002), and associate head coach (2003–2007).  He was a finalist for the Broyles Award, given annually to the nation's top college football assistant coach, in 2000.  After Michigan head coach Lloyd Carr retired following the 2007 season, Jackson was the only member of the coaching staff retained by Carr's successor, Rich Rodriguez.  When Rodriguez was fired after the 2010 season, Jackson was the only member of Rodriguez's staff retained by his successor, Brady Hoke.  Hoke and Jackson served as assistants together under Carr and Gary Moeller for a total of eight years including the 1997 national championship season.

André Bolduc: André Bolduc (born March 25, 1971 in Alma, Quebec) is a former Canadian football slotback and currently an assistant coach with the Montreal Alouettes of the Canadian Football League.  He was previously the head coach for the Université de Sherbrooke's football team, the Sherbrooke Vert et Or.  Bolduc became Sherbrooke's head coach in 2007 and led the team to its first playoff win in 2010.  He resigned as head coach following the 2011 season, citing the need to spend more time with his family.  As a professional player, he played for six seasons for the Ottawa Rough Riders, Edmonton Eskimos, and Montreal Alouettes of the CFL.  Collegiately, he played CIAU football for the Concordia Stingers.

Merle Schlosser: Merle Schlosser (October 17, 1926) was an American football player and coach.  He played college football at the end position for the University of Illinois from 1948 to 1949.  After graduating from Illinois, Schlosser was an assistant football coach under Don Faurot at the University of Missouri.  In January 1957, he was hired as the head football coach at Western Michigan University.  He held that position for seven years from 1957 to 1963.  He compiled a record of 28–33–3 as the head coach at Western Michigan.  In 1963, his team compiled a record of 2–7 and was outscored 201 to 111.  On December 27, 1963, Western Michigan's president, James W. Miller, announced that Schlosser had been fired as football coach and would be assigned to other duties in the physical education department.  He later served as the head golf coach at Western Michigan for approximately 20 years.  In September 1985, Schlosser was hired as the head golf coach at San Diego State University and held that position until May 1986.

Mike DeBord: Mike DeBord (born February 7, 1956) is an American football coach who currently serves as the associate head coach and offensive coordinator at Indiana University.  DeBord was the head football coach at Central Michigan University from 2000 to 2003, compiling a record of 12–34.  He worked as an assistant coach at the University of Michigan for a total of 11 seasons, from 1993 to 1999 and again from 2004 to 2007.  He was the offensive coordinator for the Michigan Wolverines for five seasons (1997–1999, 2006–2007) including Michigan's 1997 campaign, in which the team won a national championship.  DeBord has also worked as an assistant coach in the National Football League (NFL), with the Seattle Seahawks (2008–2009) and the Chicago Bears (2010–2012).

Fred Campbell (basketball): Fred Gaines Campbell (August 8, 1920 – December 3, 2008) was an American professional basketball player and coach as well as minor league baseball player.  He played in the National Basketball League for the Detroit Gems and Detroit Vagabond Kings.  While playing for the Gems he served as the head coach during the second half of the season after coach Joel Mason resigned.  In many seasons with the Vagabond Kings, except for the only one in which the franchise played in the NBL (the rest of the years they were independent), Campbell also served as a player-coach.  In two seasons as an NBL player, Campbell averaged 5.8 points per game.

Bo Schembechler: Glenn Edward "Bo" Schembechler Jr. (April 1, 1929 – November 17, 2006) was an American football player, coach, and athletics administrator.  He served as the head football coach at Miami University from 1963 to 1968 and at the University of Michigan from 1969 to 1989, compiling a career record of 234–65–8.  Only Joe Paterno and Tom Osborne have recorded 200 victories in fewer games as a coach in major college football.  In his 21 seasons as the head coach of the Michigan Wolverines, Schembechler's teams amassed a record of 194–48–5 and won or shared 13 Big Ten Conference titles.  Though his Michigan teams never won a national championship, in all but one season they finished ranked, and 16 times they placed in the final top ten of both major polls.

Bud Middaugh: Forest L. "Bud" Middaugh (born c. 1939) is a former American baseball coach.  He was the head baseball coach at Miami University in Oxford, Ohio from 1968 to 1979 and at the University of Michigan from 1980 to 1989.  He compiled a record of 359-173 at Miami, leading the Redhawks to three Mid-American Conference championships and four appearances in the NCAA playoffs.  In 1980, he became the head coach at Michigan.  In ten years as the head coach at Michigan, he led the Michigan Wolverines baseball team to a 465–146–1 record, seven Big Ten Conference championships and four appearances in the College World Series.  He developed several Major League Baseball players at Michigan, including Barry Larkin, Chris Sabo, Hal Morris, Scott Kamieniecki, and Jim Abbott.  Middaugh resigned as Michigan's baseball coach in June 1989 after it was revealed that he had given money collected by selling programs at football games to members of the Michigan baseball team.  Middaugh was inducted into the Miami University Hall of Fame in 1981.  Middaugh began his coaching career at Lorain Admiral King High School in Lorain, Ohio.  In three years at Admiral King, Middaugh compiled a record of 52–14 and coached his team to a Cleveland district championship and a Buckeye Conference championship.

LaVall Jordan: LaVall Jurrant Jordan (born April 16, 1979) is an American college basketball coach, currently the head coach for the Butler Bulldogs.  He is a former head coach of Milwaukee, as well as assistant coach at Michigan, Iowa, and Butler.  In six seasons as an assistant coach under Michigan head coach John Beilein, Michigan advanced to the NCAA Tournament each year, won Big Ten Conference regular season championships in 2012 and 2014 and appeared in the Elite 8 in 2014 and the National Championship in 2013.

Bobby Hauck: Robert Lawrence Hauck (born June 14, 1964) is a college football coach, currently the special teams coordinator for the San Diego State football team.  He most recently was the head coach at UNLV Rebels.  Hauck was previously the head coach at Montana, where he led the Grizzlies to seven conference titles and postseason berths in as many seasons, including three national championship game appearances.  In 2013, following three losing seasons at UNLV, Hauck led the Rebels to their first winning season since 2000.

Walt Downing: Walt Downing (born June 11, 1956) is a former American football player.  He played professional football as an offensive guard for the San Francisco 49ers from 1978 to 1983.  He played for Bill Walsh and was a member of the 1981 San Francisco 49ers team that won the franchise's first Super Bowl.  He also played for the Denver Gold in the USFL.  Downing played college football for Bo Schembechler at the University of Michigan from 1975 to 1977.  He was a co-captain of the 1977 Michigan Wolverines football team and was selected that year as a first-team All-American.

Supporting paragraphs: Walt Downing Bo Schembechler
Answer: 21