In the 1971–72 NBA season, the Lakers hired former Celtics star guard Bill Sharman as head coach. Sharman introduced morning shoot-arounds, in which the perennial latecomer Chamberlain regularly participated, in contrast to earlier years with Schayes, and transformed him into a defensive-minded, low-scoring post defender in the style of Russell. Sharman told Chamberlain to use his rebounding and passing skills to quickly initiate fastbreaks to his teammates. While no longer being the main scorer, Chamberlain was named the Lakers' new captain. After rupturing his Achilles tendon, perennial captain Baylor retired and was replaced with Chamberlain.

Initially, Sharman wanted Chamberlain and West to share this duty but West declined, stating he was injury-prone and wanted to concentrate on the game. Chamberlain accepted his new roles and posted an all-time low 14.8 points per game but also 19.2 rebounds per game, and led the league with a .649 field-goal percentage. Powered by his defensive presence, the Lakers had an unprecedented 33-game winning streak, leading to a then-record 69 wins in the regular season. According to Flynn Robinson, after the record-setting streak, Lakers owner Cooke sought to reward each of his players, who may have been expecting a trip to Hawaii, with a $5 pen set. In response, Chamberlain had everybody put the pens in the middle of the floor and stepped on them.

In the playoffs, the Lakers defeated the Chicago Bulls then played against the Milwaukee Bucks, who were led by young center and regular-season MVP Kareem Abdul-Jabbar (formerly Lew Alcindor). Life called the matchup between Chamberlain and Abdul-Jabbar the greatest matchup in all sports. Chamberlain helped the Lakers defeat Abdul-Jabbar and the Bucks in six games, and he was lauded for his performance in Game 6, which the Lakers won 104–100 after trailing by 10 points in the fourth quarter. Chamberlain scored 24 points, grabbed 22 rebounds, played all 48 minutes, and outsprinted the younger Bucks center on several late Lakers fast breaks. West called it "the greatest ball-busting performance I have ever seen". Time stated, "In the N.B.A.'s western division title series with Milwaukee, [Chamberlain] decisively outplayed basketball's newest giant superstar, Kareem Abdul-Jabbar, eleven years his junior".

In the NBA Finals, the Lakers again met the New York Knicks, who were shorthanded after losing 6-foot-9-inch (2.06 m) Reed to injury, and undersized 6-foot-8-inch (2.03 m) Jerry Lucas had to defend against 7-foot-1-inch (2.16 m) Chamberlain. Prolific outside shooter Lucas helped New York to win Game 1, hitting 9 of his 11 shots in the first half. In Game 2, which the Lakers won 106–92, Chamberlain put Lucas into foul trouble and the Knicks lost defensive power forward Dave DeBusschere to injury. In Game 3, Chamberlain scored 26 points and grabbed 20 rebounds for another Lakers win.

In a fiercely battled Game 4, Chamberlain was playing with five fouls late in the game. Chamberlain had never fouled out in his career, a record for which he was very proud. Despite the risk of fouling out, Chamberlain played aggressive defense, and blocked two of Lucas' shots in overtime, proving wrong those who said he only played for his own statistics. He also scored a game-high 27 points and, at one point, fell on his right hand, and was thought to have sprained it, but it was broken.

For Game 5, Chamberlain's hands were packed into thick pads that were normally used by defensive linemen in football; he was offered a painkilling shot but refused for fear he would lose his shooting touch if his hands became numb. Chamberlain recorded 24 points, 29 rebounds, 8 assists, and 8 blocked shots; announcer Keith Jackson counted the blocks during the broadcast. Chamberlain's all-around performance helped the Lakers win their first championship in Los Angeles with a decisive 114–100 win. Chamberlain was named the Finals MVP, and admired for playing while injured.