Duncan collected 23 points, nine rebounds and seven blocks as the Spurs used stifling defense in the first half to coast to a 101-78 rout of the Seattle SuperSonics in Game Five of their Western Conference first-round series.
San Antonio will visit the Los Angeles Lakers on Sunday in the opener of the conference semifinals. It is the fourth time in the last five years the Spurs have advanced to the second round and Duncan improved to 4-0 in first-round series -- he missed the 2000 series with Phoenix with a torn left lateral meniscus.
Duncan, who missed Game Four due to his father's death, scored six points and rookie Tony Parker added five as San Antonio jumped out to an 11-2 lead. Seattle's offense sputtered throughout and the Sonics did not reach double figures until a layup by Gary Payton with just three seconds left in the opening quarter got them within 25-10.
"We came out from the get go," Duncan said. "We were hyped up and excited to be here. We jumped on them early and put them on their heels."
Duncan scored seven points in a 16-5 spurt to close the half as San Antonio built a 55-26 halftime cushion. Seattle's 10 points in the first quarter and 26 points at halftime were team playoff franchise lows.
Payton scored 13 points in the first half, equaling the output of his teammates. Seattle had just five baskets in the first quarter and six in the second as it shot just under 30 percent (11-of-37) in the first 24 minutes.
"In the first quarter, we just missed shots and they executed," Payton said. "We didn't make shots and that was that."
Malik Rose scored 18 points and Parker finished with 15 for San Antonio, which placed five players in double figures. The Spurs held a commanding 52-30 edge in points in the paint.
San Antonio again played without starting center David Robinson, who was out for the fourth straight game with a lower back sprain. Robinson had indicated that his return was possible but the team determined that his health was still questionable.
For Duncan, it was an emotional return after a grueling week. His father, William, passed away on Monday and Duncan attended the funeral in the Virgin Islands on Thursday.
"It's been a whirlwind," Duncan said. "It's been a tough couple of days. That's an understatement. I've had great support from my family and my friends."
"When he steps on the court, he concentrates on basketball," Spurs coach Gregg Popovich said. "Nothing throws him off, he's a stoic character, but I bet he knows what he's feeling."
Rose tried to step it up in Duncan's absence in Game Four and poured in playoff career highs of 28 points and 13 rebounds. He responded with another strong game with Robinson out and made 8-of-14 shots and grabbed 13 rebounds.
Steve Smith scored 14 points and led the Spurs with six assists. Parker drilled three 3-pointers and was able to fend off the defense by Payton by not turning the ball over. San Antonio committed just seven turnovers and held a 53-39 edge on the glass.
The crowd responded to Duncan's presence with a huge ovation and San Antonio responded. The fans later chanted "MVP" when Duncan exited in the fourth quarter.
"I don't think there should be any doubt who the Most Valuable Player in the league should be," Spurs guard Antonio Daniels said. "I've said that game in and game out. We'll just have to see what happens."
Payton led Seattle with 23 points but made just 8-of-26 shots. Brent Barry was the only other Sonic in double figures with 12 as Seattle shot 34 percent (29-of-85) and never was a factor.
The Sonics got a minimal contribution from its frontcourt tandem of Desmond Mason and Vladimir Radmanovic. Mason made just 4-of-13 shots for nine points and Radmanovic made 3-of-12 for seven after scoring 23 in Game Four.
"I thought the first quarter would be very important," Seattle coach Nate McMillan said. "I knew the (Spurs) would be playing on emotion. It was do-or-die and they got the crowd into it."
San Antonio will be trying to avenge a four-game sweep by the Lakers in last season's conference finals. The Spurs lost three of four meetings with Los Angeles in the regular season.