The flight took off with about 1:20 remaining in the 115-109 victory Tuesday at the American Airlines Center in Dallas. Smith stole a pass from the Blazers and sprinted down the court in pursuit. He collected the ball inside the 3-point line. Smith used his first touch to bounce the ball hard in the paint.
He caught the self-pass in mid-air and threw down a slam, giving the Mavericks a 107-99 advantage.
The Mavericks' rookie said he planned on doing something else on the dunk, but had a miscue.
"Yeah, it was a bad pass," Smith said. "I just got a break, was wide open and had a lot of time. So that just happened. I threw a bad pass."
"Just spur of the moment, aside from that I think we did a really good defensively tonight."
Smith led the Mavericks with 18 points. He also had eight assists and eight rebounds. Damian Lillard led the Blazers with 29 points.
The Mavericks are currently the No. 13 team in the Western Conference. Dallas faces the Orlando Magic at 7 p.m. Wednesday at the Amway Center in Orlando.
Smith ranks in the top four in points and assists among all NBA rookies.