THE NBA PLAYOFFS : Lakers Come Off Floor to Deck Mavericks : Game 5 Win Breaks Down Dallas, 119-102

They may stage rodeos at the Forum, but the notion that the Lakers were ripe for a last roundup exploded in a purple and gold cloud of dust Tuesday night.

When last seen, the Dallas Mavericks were being herded back to Texas like so many dogies by the Lakers, who punched the swagger right out of the cowboys, 119-102, to take a 3-2 lead in the best-of-seven Western Conference finals.

“We approached this game like the Sioux, the Cheyenne and the Apaches approached the battle of Little Big Horn,” Mychal Thompson said. “We came out to collect no prisoners--only scalps.”

Game 6 is scheduled for Thursday night in Dallas, where the Mavericks had knocked the Lakers off their high horse with two one-sided wins last weekend. But whatever momentum the Mavericks thought they’d brought with them here disappeared in a Laker fast-break stampede that began with the home team’s first basket of the game--A.C. Green sneaking away for a jam off a full-court pass by Magic Johnson--and never let up, despite a scary face-first takedown of Byron Scott by Dallas forward Sam Perkins in the first quarter.

“It was like a vitamin pill,” said Magic Johnson, who hardly seemed to need any extra energizing in a 20-assist, 15-point performance. “It lifted us up. It made us even crazier.”

Badly outrebounded by the Mavericks in the Dallas, the Lakers on the rebound made the whole issue a moot point by shooting the lights out, hitting 60% of their shots--66.7% in the first half, when they took a 17-point lead, 64-47.

The Mavericks, who had been overrun here in the first two games last week, appeared undaunted by their hostile surroundings at the outset, scoring on their first five possessions, but couldn’t pull the trigger on a run of 15 straight Laker points in the first quarter.

“I don’t know what it is,” said Dallas guard Rolando Blackman of the Mavericks’ Forum foldups, which now number nine out of nine in postseason play.

“I don’t think they have any leprechauns like at the Boston Garden, but they definitely have something here. It’s a feeling they thrive on.”

The Lakers were feeling a whole lot better when a six-point lead at the end of the first quarter, 33-27, soon ballooned to 16, 47-31, after consecutive steals and breakaway baskets by James Worthy and Michael Cooper. Worthy slapped a pass away from Dallas center James Donaldson and went in for the jam, then Cooper picked Donaldson clean and dribbled in for the layup.

Worthy had 28 points to lead the Lakers, including 10 points in the third quarter, when the Lakers expanded their lead to 21, 92-71. Magic Johnson had 15 points and 20 assists, Kareem Abdul-Jabbar scored 21 points--including a couple of baskets where his 41-year-old legs were the first down the floor on the break--while Green had 16 points and 10 rebounds before retiring to the bench with leg cramps in the fourth quarter.

The Mavericks, who had relied on deadly perimeter shooting and Roy Tarpley’s rebounding in their two wins in Dallas, shot more blanks than baskets Tuesday. Derek Harper, who scored 35 points in Sunday’s win, and backcourt mate Blackman shot a combined 5 for 17 in the first half, 12 for 32 for the game.

Mark Aguirre had 31 points to lead Dallas, but Tarpley’s 18 points and 11 rebounds wreaked nowhere near the havoc they had in Dallas. And by the fourth quarter, which had been the Mavericks’ domain in the last two games, the Lakers had stuffed this one safely away.

Laker Coach Pat Riley would love nothing better than the same approach in Dallas.

“We want to come out with pressure,” he said. “If everyone fouls out in the first period, I don’t care.”

By retaliating for Perkins’ clothesline takedown of Scott in the first quarter, Cooper risked turning Dallas’ “Shout Party” Thursday in Game 6 into a potential lynch mob.

These teams were less than a mutual admiration society to begin with. Tarpley has been something of a Dennis Rodman West with his gesturing and barking at Laker players, especially Cooper. Scott resented a magazine article that rated the Dallas backcourt as the best in the league. Green looks like he has been taking glare lessons from Maurice Lucas, and Aguirre hasn’t cared for the way Green has been trying to squeeze inside his jersey on defense. After an animated chin-to-chin chat on the subject in the first quarter, both players were assessed a technical foul.

And Worthy hasn’t been happy at the suggestion that maybe Jerry Buss should have traded him for Tarpley when he had the chance two years ago.

“I get tired of hearing about it,” said Worthy, whose fatigue obviously did not extend below his ears Tuesday night. “It seems like they bring it up every year. It’s history now.”

But emotions jumped off the scale during a 15-0 Laker run in the first quarter, when Worthy rebounded a missed jumper by Perkins and broke out of the Dallas end at full gallop. When he reached the top of the circle, he dumped a pass on the right wing to Scott, who went airborne toward the basket.

He was intercepted in midflight, however, by Perkins, whose wrestle hold around Scott’s neck resulted in a terrifying crash landing, Scott hitting the floor face first.

When the Laker guard regained his feet, he went straight for Perkins, who looked stricken by what had happened. Magic Johnson kept Scott away, however, and order appeared to be restored.

“He acted like Henry the Eighth trying to behead Byron,” Thompson said. “It was uncalled for. It was like a Hulk Hogan clothelsine.”

But with the Lakers ahead by 21 points and the first half winding down, Cooper took it upon himself to be the avenging Laker. With Harper ahead of the pack and going in for an uncontested layup, Cooper hacked the Dallas guard with his right hand, then put his left hand on the back of Harper’s head and shoved him to the floor.

Cooper was called for a breakaway foul, which gave Harper two free throws--he made them both--and Dallas the ball. Brad Davis made a driving basket to complete a four-point play, but that merely trimmed the Lakers’ halftime lead to 64-47.

Whatever fury Dallas may have taken into the dressing room at intermission wasn’t apparent at the start of the third quarter, as the Lakers hit their first four shots in an 8-2 run that extended the Laker lead to 23, 72-49, before Dallas Coach John MacLeod called timeout with 10:03.

Johnson did most of the stuffing in the second quarter, when he personally accounted for 13 Laker points in a row to inflate a 12-point lead, 49-37, into a 21-point cushion, 62-41, with 1:57 left in the half.

Johnson threaded a pass to Thompson (6 points, 9 rebounds) for a shot off the glass, then kicked a pass back to Thompson for a 17-footer. After Thompson blocked a shot by Detlef Schrempf at the other end, Johnson knocked in two straight push shots from 19 feet away.

Worthy, who had 6 assists and 6 rebounds to complement his 12 of 18 shooting, grabbed a rebound of a miss by Harper, then sprinted ahead for another Magic pass and a lay-in, giving the Lakers 8 straight points and a 59- 39 lead.

Aguirre countered with offensive rebound and basket, but Johnson set up for a three-pointer, hitting from 25 feet away. The Laker lead was 21, and the Forum crowd responded with a 21-cocktail salute.

“We have a motto,” Riley said. “We will not lose at home. Even if we shoot 35% and get outrebounded by 20, we’ll find a way to win at home.”

If the Mavericks have a similar motto, they had better live up to it Thursday...or die trying.

Laker Notes If a seventh game is necessary, a limited number of tickets will go on sale Friday at the Forum at 10 a.m. Priority numbers determining the ticket line will be distributed at random at 8. Should the Lakers win the series in six games, tickets for the first two games of the finals will go on sale Friday, with the same procedure in effect. . . . Looking for a bad omen? The last two seasons in which the Lakers defeated the Mavericks in the playoffs, 1984 and 1986, the Lakers lost in the championship finals. . . . The Lakers were 9-0 in playoff games in which they shot 50% or better, 0-5 when under 50%. . . . The total of 19 turnovers in Game 4 Sunday (Lakers 10, Mavericks 9) was just one more than the all-time NBA playoff low.