[15] Wake Forest University basketball coach Dave Odom, in particular, grew interested in Duncan after the 16-year-old allegedly played NBA star Alonzo Mourning to a draw in a 5-on-5 pick-up game.

[11] In the year before Duncan's arrival at Wake Forest University, the Demon Deacons had reached the Sweet 16, but then lost leading scorer Rodney Rogers, who entered the 1993 NBA draft.

[17] Duncan struggled with early transition problems and was even held scoreless in his first college game, but as the year progressed, he and teammate Randolph Childress led the Deacons to a 20–11 win–loss record.

"[16] Duncan also established his reputation as a stoic player, to the extent that opposing fans taunted him as "Mr. Spock", the prototype of a logical, detached character from Star Trek.

[16] In the 1994–95 NCAA season, the sophomore was soon called one of the best prospects among those eligible for the NBA, along with peers Joe Smith, Rasheed Wallace, and Jerry Stackhouse.

[11] In that season, he led the Demon Deacons into the Atlantic Coast Conference (ACC) championship game against the Rasheed Wallace-led North Carolina Tar Heels.

[11] In the 1996–97 NCAA season, new 7 ft 1 in (2.16 m) Demon Deacon and future NBA player Loren Woods eased the pressure on Duncan close to the basket.

[23] Later, during the NCAA tournament, Stanford University, led by future NBA point guard Brevin Knight, eliminated Wake Forest with a 72–66 win.

He earned first-team All-American honors for the second time and was a unanimous pick for both the Oscar Robertson Trophy and Naismith College Player of the Year.

[25] In contrast to contemporary prep-to-pro players like Kevin Garnett, Jermaine O'Neal, Tracy McGrady, and Kobe Bryant, Duncan stayed in college for a full four years.

Overall, Duncan led his team to a 97–31 win–loss record and finished his college career as the all-time leading rebounder in NCAA history in the post-1973 era (a mark later surpassed by Kenneth Faried).

[44] Sports Illustrated journalist and retired NBA player Alex English added: "Duncan came up big each time they went to him with that sweet turnaround jumper off the glass.

[7] In the 2001 NBA playoffs, the Spurs eliminated the Timberwolves 3–1, defeated the Dallas Mavericks 4–1, but then bowed out against the Lakers (led by superstars Shaquille O'Neal and Kobe Bryant) in four straight games.

[48] On the other hand, Duncan's team struggled with the fact that the aging Robinson was no longer able to sustain his level of performance, and backup center-forward Malik Rose had to step in more often.

[51] He averaged 23.3 points, a career-high 12.9 rebounds, 3.9 assists and 2.9 blocks per game, and earned All-NBA and All-Defensive First Team recognition, resulting in his second NBA Most Valuable Player Award.

Coming off the bench were clutch shooting power forward Robert Horry, versatile Hedo Türkoğlu and veterans Malik Rose and Kevin Willis.

[59] Statistically though, Duncan remained strong; after another convincing season with averages of 22.3 points, 12.4 rebounds, 3.1 assists and 2.7 blocks,[7] he led the Spurs into the Western Conference Semifinals.

There, they met the Los Angeles Lakers again, split the series 2–2, and in Game 5, Duncan made a toughly defended jump shot which put the Spurs ahead by one point with 0.4 seconds left to play.

Despite scoring 39 points in regulation time and fouling out both Dampier and Keith Van Horn, Duncan only made one of seven field goal attempts in overtime against Mavericks reserve center DeSagana Diop, and the Spurs lost Game 7.

[76] However, arch-rivals Los Angeles Lakers defeated San Antonio in five games in the Conference Finals, and the Spurs once again failed to capture back-to-back NBA championships.

[78] Despite Duncan having problems with his knee and the team losing the services of shooting guard Ginóbili for most of the season, San Antonio qualified for the playoffs as the third seed with a 54–28 record.

[79][80] Coupled with an aging supporting cast (Bowen, Michael Finley and Kurt Thomas were all in their late 30s), however, the Spurs were only considered fringe contenders for the championship.

[81] With the Spurs looking to provide a more solid supporting cast in the 2009–10 season, they acquired Richard Jefferson, Theo Ratliff, Antonio McDyess, DeJuan Blair, and Keith Bogans.

[91] Although Duncan produced career lows in points and rebounds per game, the Spurs ended the regular season as the first seed in the West for the 2011 NBA playoffs, and were second in the league (to Chicago).

[92] Prior to a game against the Philadelphia 76ers on March 24, 2012, head coach Gregg Popovich decided to give Duncan a night off by listing him on the official scorecard as "DNP-OLD", poking fun at his 36-year-old body.

On May 31, 2012, in the third game of the Western Conference Finals against the Oklahoma City Thunder, Duncan set the record for most career blocks in playoffs history, surpassing Kareem Abdul-Jabbar.

[97] On December 2, 2013, Duncan became the oldest player to record a 20–20 game in NBA history, finishing with 23 points, 21 rebounds, and the game-winning jump shot against the Atlanta Hawks.

It was also the first time since NBA players became eligible that the U.S. men's basketball team lost a game in international competition and returned home without gold medals.

"[142] Sports journalist Kevin Kernan commented on his ability to relax and stay focused, stating that having a degree in psychology, Duncan often not only outplays, but out-psychs his opponents.

[160][161][162] He made his debut as acting head coach on March 3, 2020, leading the Spurs to a 104–103 comeback win over the Charlotte Hornets, which Popovich missed for personal reasons.