DALLAS — Now that Jason Kidd is in charge of calling plays for the Dallas Mavericks, he’s bringing a simple approach: “Whoever is open, shoot it.”

That easy, huh?

The Mavs are making it look that way, improving to 4-0 since Kidd took over with a 104-99 victory over the Portland Trail Blazers on Wednesday night.

Dallas is making well over 50 percent of its shots during this surge, breaking 100 points every game. The Mavericks also have kept every foe under 100. The last three wins have come against teams with winning records; that includes a win at Orlando and now this one against a team that had won five straight and that’s ahead of them in the Western Conference playoff chase. They’ll be tested again Thursday night in Utah.

“We believe in one another,” said Kidd, who had 10 assists and a major milestone, passing Oscar Robertson for fourth on the NBA’s career assists list. “We believe defensively and offensively that we can go out there and get some wins. The guys are playing at a high level and we are having fun doing it.”

Josh Howard got Dallas going early and Jason Terry pulled them through late, but it was a team effort. Brandon Bass made nine of 11 shots for 19 points, Dirk Nowitzki had 16 points and 11 rebounds, and Antoine Wright had 11 points and some solid defense on Portland’s Brandon Roy. Kidd did, too, along with scoring seven points and grabbing seven rebounds.

“I think (Kidd) brought an air of confidence to our team during some periods whn we were struggling,” Mavs coach Rick Carlisle said.

Roy still scored 26 points, but that included a pair of 3-pointers in the final minute, which made things a bit more interesting but didn’t change the outcome. Portland lost its 11th straight in Dallas.

“It’s frustrating because we want to take that next step as a team,” Roy said. “We know we have to get better, especially on the road, if we want to be one of the top teams.”

Local native LaMarcus Aldridge added 21 for the Trail Blazers. Jerryd Bayless had 14, Travis Outlaw 13 and Rudy Fernandez 12.

“Our starts, we’ve got to get better there and limit our mistakes,” Portland coach Nate McMillan said. “We played a veteran team and they executed. We’ve got to be more aggressive.”

Howard scored 23 points, his most since Dec. 30. He had 15 in the game’s first 15 minutes to help Dallas go ahead by as many as 16. But Roy helped the Trail Blazers — who have the most fourth-quarter comebacks in the NBA this season — get within 86-81 with 7:00 left.

Terry then fed Kidd for a 3-pointer, then blocked a shot and turned it into a fast-break layup. Kidd followed with a tough running jumper that put Dallas back up by 10, prompting a time out by Portland. Terry turned toward fans, smiled and raised his arms to draw cheers. He finished with 20 points.

Carlisle made the mistake of thinking the game was over before it really was. Up by nine in the final minute, he went with several deep reserves only to see Roy hit a pair of 3-pointers. Suddenly, it was 100-97 and Nowitzki and Kidd were headed back onto the court with 10.4 seconds left.

Nowitzki was fouled away from the ball with 7.7 seconds left, giving the Mavs one shot and the ball. Nowitzki missed — for only the sixth time in his last 17 games — but then Terry made a pair of foul shots with 7 seconds to go.

Fernandez got fouled taking a 3-pointer with 4 seconds left. He made the first, missed the second and then seemed to try missing the third but hit it; his disappointment evidenced by slumped shoulders. Nowitzki finally sealed things with two free throws with 2.6 ticks left.

“It’s an example of needing to respect the talent in this league,” Carlisle said.

Notes: Dallas shot 55.1 percent; the Mavs were at 67.4 percent

midway through the third quarter. … After getting an NBA season-high 21 steals the previous game, the Trail Blazers had six. … Kidd has 9,895 career assists. Next up: Magic Johnson, who had 10,141 assists. Kidd could catch him by season’s end. … Dallas has won 17 of the last 19 meetings, with both of Portland’s wins coming last season. The Mavs lead the season series 2-0, with one meeting left.