Question: The 1989–90 NBA season was the Bulls' 24th season in the National Basketball Association, despite their solid playoff run last year, the Bulls fired head coach Doug Collins and replaced him with who, a former American professional basketball player, coach and executive in the National Basketball Association (NBA)?
Context: The 1997–98 NBA season was the Pistons' 50th season in the National Basketball Association, and 41st season in the city of Detroit.  Despite signing free agents Brian Williams and Malik Sealy during the offseason, the Pistons got off to a slow start with a 6–11 record as Joe Dumars missed ten games due to hamstring and shoulder injuries.  In late December, they traded Theo Ratliff and Aaron McKie to the Philadelphia 76ers for Jerry Stackhouse and Eric Montross.  At midseason, head coach Doug Collins was fired after a 21–24 start, and was replaced with Alvin Gentry.  Collins would later on get a job as color analyst for the "NBA on NBC".  Despite another stellar season from Grant Hill, who was selected for the 1998 NBA All-Star Game, the Pistons missed the playoffs finishing sixth in the Central Division with a 37–45 record.  Following the season, Sealy signed as a free agent with the Minnesota Timberwolves, Grant Long re-signed with the Atlanta Hawks, and Rick Mahorn re-signed with the Philadelphia 76ers. The 1989–90 NBA season was the Mavericks' 10th season in the National Basketball Association.  A year after missing the playoffs, the Mavericks fired head coach John MacLeod at the end of November, replacing with him Richie Adubato.  They finished third in the Midwest Division with a 47–35 record.  Rolando Blackman was selected for the 1990 NBA All-Star Game.  However, things would not all go smoothly for the Mavericks as Roy Tarpley found himself in hot water again, as he was arrested in November for driving under the influence of drugs.  During the final month of the season, the team released Adrian Dantley to free agency.  In the first round of the playoffs, the Mavericks were swept by the Portland Trail Blazers in three straight games.  This would be their final playoff appearance until 2001.  Following the season, Sam Perkins signed as an unrestricted free agent with the Los Angeles Lakers. The 1996–97 NBA season was the Pistons' 49th season in the National Basketball Association, and 40th season in the city of Detroit.  During the offseason, the Pistons re-signed free agent Rick Mahorn, who was a member of the championship team in the 1989 NBA Finals.  The team also acquired Stacey Augmon and Grant Long from the Atlanta Hawks, but later on sent Augmon to the Portland Trail Blazers for Aaron McKie at midseason.  The Pistons got off to a fast start winning ten of their first eleven games on their way to a 20–4 start.  However, they went 34–24 for the remainder of the season finishing third in the Central Division with a 54–28 record.  Grant Hill averaged 21.4 points, 9.0 rebounds, 7.3 assists and 1.8 steals per game, while finishing third in MVP voting behind Karl Malone and Michael Jordan.  Hill along with Joe Dumars, and head coach Doug Collins represented the Eastern Conference during the 1997 NBA All-Star Game. Philip Douglas Jackson (born September 17, 1945) is a former American professional basketball player, coach and executive in the National Basketball Association (NBA).  Jackson was the head coach of the Chicago Bulls from 1989 until 1998, during which time Chicago won six NBA championships.  He then coached the Los Angeles Lakers, who won five championships from 2000 until 2010.  In total, Jackson has won 11 NBA titles as a coach, surpassing the previous record of nine set by Red Auerbach.  He also won two championships as a player with the New York Knicks in 1970 and 1973, and holds the NBA record for the most combined championships (13) The 1995–96 NBA season was the Pistons' 48th season in the National Basketball Association, and 39th season in the city of Detroit.  During the offseason, the Pistons hired Doug Collins as head coach while acquiring Otis Thorpe from the Portland Trail Blazers, who won a championship as a member of the Houston Rockets in the 1994 NBA Finals.  Under Collins, the Pistons who were now led by second-year star Grant Hill and Allan Houston, played .500 basketball in the first half of the season, as the team signed free agent Michael Curry along the way.  However, Joe Dumars' production would slip as he averaged just 11.8 points per game.  The Pistons reemerged as a playoff contender finishing fifth in the Central Division with a 46–36 record, and returned to the playoffs after a three-year absence thanks to the stellar play of Hill, who was selected for the 1996 NBA All-Star Game. The Philadelphia 76ers are an American professional basketball team based in Philadelphia, Pennsylvania.  They are a member of the Atlantic Division of the Eastern Conference in the National Basketball Association (NBA).  Formerly known as the Syracuse Nationals, the 76ers joined the NBA when it was founded in 1949.  The Nationals had a record of 51–13 in their first NBA season under coach Al Cervi and won the Eastern Division crown.  The franchise were purchased by Philadelphian Irv Kosloff and Ike Richma in the spring of 1963; the NBA approved their franchise shift on May 22 and name change to the Philadelphia 76ers on August 6.  This brought professional basketball back to the city, which had been without a team since the Golden State Warriors left Philadelphia in 1962.  After coaching the 76ers since , Doug Collins resigned as head coach on April 18, 2013 following the 2012–13 season.  Brett Brown was hired to be the head coach of the 76ers on August 15, 2013 prior to the start of the 2013-14 season. The 1989–90 NBA season was the Nuggets' 14th season in the National Basketball Association, and 23rd season as a franchise.  The Nuggets got off to a fast start winning 11 of their first 15 games, on their way to a solid 19–9 start.  However, they began to show their age as they barely made the playoffs with a mediocre record of 43–39, fourth in the Midwest Division.  At midseason, the team acquired Joe Barry Carroll from the New Jersey Nets, while Fat Lever was selected for the 1990 NBA All-Star Game.  In the first round of the playoffs, the Nuggets were swept by the San Antonio Spurs in three straight games.  Following the season, an era would come to an end in Denver as head coach Doug Moe was fired, Alex English signed as a free agent with the Dallas Mavericks, while Lever was traded to the Mavericks and Barry Carroll was released. The 2001–02 NBA season was the Wizards' 41st season in the National Basketball Association.  After finishing 19–63 the previous season, the Wizards won the Draft Lottery and selected high school star Kwame Brown with the first overall pick in the 2001 NBA draft.  This season marked the return of All-Star guard Michael Jordan, who came out of his retirement to play for the Wizards.  Under new head coach Doug Collins, the Wizards struggled with a 2–9 start, but then posted a nine-game winning streak in December holding a 26–21 record before the All-Star break.  However, they lost 24 of their final 35 games finishing the season fifth in the Atlantic Division with a 37–45 record, which was an 18-game improvement.  However, they still missed the playoffs even with the help of Jordan, who was selected for the 2002 NBA All-Star Game.  Brown failed to live up to expectations averaging just 4.5 points per game off the bench. The 2003–04 NBA season was the Wizards 43rd season in the National Basketball Association, and their 31st season in the city of Washington, D.C..  With All-Star guard Michael Jordan retired for good and Doug Collins fired as head coach, the Wizards hired Eddie Jordan, and signed free agent and last year's Most Improved Player Gilbert Arenas during the offseason.  Under Jordan, the Wizards showed signs early into the season as they won their first game against the Chicago Bulls 99–74, and held the Toronto Raptors to 60 points in a 26-point margin win, while winning three of their first five games.  However, with team captain Jerry Stackhouse playing just 26 games due to knee injuries, the Wizards played mediocre basketball all season finishing sixth in the Atlantic Division with a disappointing 25–57 record, missing the playoffs for the seventh straight season.  Following the season, Stackhouse was traded to the Dallas Mavericks, and Christian Laettner signed as a free agent with the Miami Heat. The 1989–90 NBA season was the Bulls' 24th season in the National Basketball Association.  Despite their solid playoff run last year, the Bulls fired head coach Doug Collins and replaced him with Phil Jackson.  Under Jackson, the Bulls finished the regular season with a 55–27 record, averaging 109.5 points per game and being led by Michael Jordan's league-leading 33.6 ppg.  Clinching second place in the Central Division and a third seed in the playoffs, the Bulls defeated the Milwaukee Bucks three games to one in the first round, then defeated the Philadelphia 76ers four games to one in the semifinals.  They advanced to the Eastern Conference Finals before losing a seven-game series to the eventual champion Detroit Pistons.
Answer: Phil Jackson