The formal announcement will come Tuesday at a news conference, said the team official, who requested anonymity because the announcement is pending.
Nowitzki and the Mavericks went from a league-best 67 wins to a stunning first-round elimination by eighth-seeded Golden State, with the big German quite un-MVP-like for most of the series.
Voting was completed before the playoffs.
The story was first reported late Thursday by ESPN.com.
Nowitzki becomes the first MVP in 25 years not to win a single playoff series; it last happened to Houston's Moses Malone in 1981-82. That failure is likely to be remembered more than the fact he's the first European honoree, and the first not to have attended a U.S. high school or college.
Nowitzki's victory also ends the two-year reign of his good friend and former teammate, Steve Nash of Phoenix. After blossoming into star players together in Dallas, one of them has been the MVP all three seasons since they've been separated.
Nowitzki earned it this time by being the best player on the best team, leading the Mavericks in scoring (24.6 points per game) and rebounding (8.9 per game).
He was an All-Star for the sixth straight year and started the game for the first time. That was a first for a Dallas player - as is this honor. On Thursday, he was chosen to the All-NBA first team for a third straight year.
While Nowitzki's ninth season wasn't his highest-scoring, it was his most accurate. He set career highs in shooting percentage for field goals (50.2), 3-pointers (41.6) and free throws (90.4).
Nowitzki and the Mavericks came into this season driven by having blown a 2-0 lead in the NBA Finals last summer. After losing their first four games, they dropped only 11 more. They won the most games in team history and tied for sixth-most in league history. They also became the first club with three winning streaks of at least 12 games, going on spurts of 12, 13 and 17 in a row. But reputations are made in the playoffs, and that's where Nowitzki has looked so ordinary in his last two series - the finals against Miami and the one that ended last week. Pestered by smaller defenders who were armed with the insight of coach Don Nelson, Nowitzki's coach his first seven seasons, the Warriors limited him to 19.7 points per game on 38 percent shooting. His 3-point accuracy plummeted to 21 percent. In the series finale, Nowitzki scored just eight points on 2-of-13 shooting after having dramatically helped the Mavs avoid elimination in the closing minutes of the previous game. The combination of last year's collapse against Miami and the Golden State flop have sparked wide debate about whether Nowitzki is capable of leading a team to a title. However, this award is a chance to reflect on the amazing ride that's gotten him to this point. Growing up in Wurzburg, Germany, his father a successful handball player and his mother a former member of the national basketball team, Nowitzki was discovered at age 16 by Holger Geschwindner, captain of West Germany's 1972 Olympic team.
When Nowitzki said he wanted to get serious about learning the game, Geschwindner devised an unusual training regimen aimed at producing an usual basketball specimen: A 7-footer who shoots 3-pointers.
The Mavericks were wowed by Nowitzki's skills when he worked out at their gym before going to a youth tournament in San Antonio at the 1998 Final Four. They acquired him in a draft-day deal with Milwaukee, which had taken him ninth overall on orders from Dallas.
Playing for Nelson, a wizard of the mismatch, Nowitzki became a nearly 22-point per game scorer by his third season. He's remained at or above that level ever since. He's already the leading rebounding in club history and is on pace to become the leading scorer next season. This season, he became a more reliable passer, averaging a career-best 3.4 assists per game. He even flirted several times with his first career triple-double. He's also become a solid defender, shaking the mocking name of "irk," as in there being no "D" in him. Nowitzki turns 29 next month.
, so he should have plenty more chances to fix his current playoff reputation.