The Spurs will hold a news conference at 4:30 Eastern Time to celebrate the naming of Duncan as the franchise's first league MVP since center David Robinson won the award in 1994-95.
The voting, conducted among 126 media members from across the country, has not yet been made available by the league.
Word leaked out on Monday that the 7-foot Duncan had won the award with Nets point guard Jason Kidd finishing second.
Duncan, 26, ranked among the league leaders with 25.5 points (fifth-best), 12.7 rebounds (second) and 2.4 blocks (fourth) per game to help San Antonio win the Midwest Division title with a 58-24 record, the second-best mark in the Western Conference.
Kidd, 29, was acquired from the Phoenix Suns for guard Stephon Marbury last summer and helped the Nets improve from 26-52 to 52-26, the franchise's best regular season record, and capture their first Atlantic Division title.
Scott believes Kidd's impact on the Nets should have been enough to win the award, although Kidd averaged just 14.7 points and shot 39 percent from the field.
"It's ridiculous. I don't understand it," Scott said Tuesday before the Nets beat the Charlotte Hornets in Game Two of their Eastern Conference semifinal series. "It's making it a little hard for me to understand what's the criteria, what do you have to do? I'm not trying to say that Tim doesn't deserve it. He's a great player. But San Antonio wins 53, 54, 55 games every season. What Jason has done with our team, from where we've come from. I don't understand it."
Nets President Rod Thorn also expressed his disappointment with Kidd's runnerup status.
"If you told me Tim Duncan was voted as the most outstanding player in the NBA, I would have no problems," Thorn said. "But my definition of the Most Valuable Player is a guy who has done more for his team than in any given year. With that definition, I'm very disappointed that Jason didn't win it."
Duncan clearly emerged as the leader of the Spurs this season, enjoying his best season, while fellow 7-footer Robinson had the lowest output of his career in points, rebounds and blocked shots.
Duncan led the team in scoring in 72 of 82 games and in rebounding 69 times. He also took what was his one weakness, his 62 percent shooting from the free throw line last season, and turned it into a strength, making nearly 80 percent from the line.
With the departure of veteran point guard Avery Johnson, Duncan also became more of a vocal leader this season for the Spurs.
Tony Parker, the team's 19-year-old point guard, often credits Duncan for pushing him to be more aggressive.