Rapid Reaction: Pacers 103, Mavericks 78

How it happened: By the end of the third quarter, the Dallas Mavericks had long faces. It was apparent by then that their long beards weren’t getting whacked Thursday night.

The Mavs’ defensive deficiencies, which had been masked recently by Dallas’ remarkable efficiency on the other end, got exposed in the third quarter, when the Pacers turned a halftime tie into a lopsided lead by lighting it up for 34 points in that frame. Indiana shot 70 percent in the quarter, hitting 14 of 20 shots from the floor.

The Mavs, meanwhile, shot 30 percent (6-of-20) and barely managed to outscore Indiana’s Paul George in the third. The Mavs had 17 points in the quarter; the Pacers’ young All-Star wing had 13 of his game-high 24 points.

The Mavs trimmed the lead to 10 points early in the fourth quarter, but they never made a serious run.

Dirk Nowitzki scored 21 points on 10-of-20 shooting, but this was otherwise a dreadful offensive night for Dallas against the NBA’s stingiest scoring defense. It was the first time the Mavs failed to score at least 80 points since a Dec. 14 loss to the Toronto Raptors.

The Mavs were physically overmatched against the bigger, stronger Pacers all night. Indiana had a 55-34 rebounding advantage and a 50-34 edge in points in the paint.

What it means: The Mavs aren’t shaving on this homestand. More importantly, they didn’t make up any ground on the Los Angeles Lakers, who lost in Milwaukee. Dallas (35-37) is a game and a half behind the eighth-place Lakers and a game behind the Utah Jazz, who were idle Thursday.

Play of the game: A miserable third quarter for the Mavs ended with ex-Dallas big man Ian Mahinmi throwing down a two-hand dunk. Pacers backup guard Orlando Johnson found a cutting Mahinmi wide open in the paint for the way-too-easy bucket.

Stat of the night: The Pacers are an NBA-best 14-7 on the second night of back-to-backs. The Mavs fell to 12-3 at home against teams that played the previous night.