Lakers swept into season of uncertainty

The Lakers’ season ended amid a firestorm of “Beat L.A.” chants and a complete undoing at the hands of the Dallas Mavericks in a surprisingly early phase of the NBA playoffs.

The Mavericks won Game 4 of the Western Conference semifinals Sunday, 122-86, and it could only get worse for the Lakers in what will surely be a long, agonizing off-season.

Their roster is aging. Their team looks slow. Their spending power is hamstrung by salary-cap guidelines that might get tighter with 22 of 30 teams claiming to lose money this season.

Photos: Mavericks sweep Lakers

The Lakers checked into training camp last September with the potential for a rare “three-peat” after winning two consecutive championships.

Instead they were swept away by Dallas, failing to win a game in the series as Mavericks fans joyously sung along to a goofy scoreboard ditty, “Mamas, don’t let your babies grow up to be Lakers fans.”

It was a macabre ending to the Phil Jackson era, the Lakers’ 65-year-old coach firmly stepping away from what he called throughout the season his “last stand.” As he walked off the court for a final time, he offered a wave before disappearing into a tunnel at American Airlines Center.

He met with reporters 20 minutes later and didn’t seem nostalgic. It’s not his nature. He failed to add to his record of 11 championships as a coach but predicted future success for the franchise.

“The Lakers are going to survive and do well,” he said.

But … how?

They already have the NBA’s highest payroll ($91 million) and are too far over the salary cap to sign any top-tier free agents until 2014.

Their main vehicle for rebuilding will have to be by trades because they don’t have a first-round pick in next month’s draft and can sign only a mid-level free agent.

After they pick a successor for Jackson, the Lakers have a very big decision to make. Is Andrew Bynum their future?

The 23-year-old is already one of the top centers in the game, but his balky knees make him a long-term risk for the Lakers … and any would-be takers in a trade.

Bynum is their only player under 30 with any trade value.

Dwight Howard could be the biggest player to change teams in the next year or two, the charismatic Orlando center failing to even get out of the first round of the playoffs with his underachieving team this season.

So what needs to happen to get the Lakers back on championship track?

“I don’t know,” Kobe Bryant said. “That’s Mitch’s job.”

That would be Mitch Kupchak, the Lakers’ general manager. He declined to comment Sunday on the future of the team.

Lakers executive Jeanie Buss, the daughter of team owner Jerry Buss, tried to sound hopeful on a Twitter dispatch after the game.

“We will be back,” she wrote before referring to her father in the third person. “Dr. Buss knows how to fix things.”

The Lakers, and Buss, have a reputation of retooling with remarkable quickness, but this would be a serious fix.

The Lakers have eight players over 30 under contract next season, just the beginning of their issues.

Bryant, 32, will be back despite showing shades of mortality against Dallas, including consecutive 17-point efforts in the last two games. The remainder of his contract — three years, $83.5 million — is too weighty to trade, and it would be an unpopular public-relations move by the team to jettison him.

Another problem for the Lakers: There are other bulky and fully guaranteed contracts on their payroll.

Pau Gasol, 30, has three more years and $57 million remaining on a deal that doesn’t look as solid after he averaged a meager 13.1 points and 7.8 rebounds in the playoffs.

Enigmatic forward Ron Artest, 31, has three more years and $21.5 million remaining. Backup players Steve Blake, 31, and Luke Walton, 31, will cost the team a combined $23.5 million before their contracts expire.

Versatile forward Lamar Odom, 31, has two more years at a comparatively affordable total of $17 million, making him possible trade bait.

Turning everything a shade murkier is the likelihood of a work stoppage at the end of June. Negotiations between NBA players and owners are at a standstill, making the traditional trade period in July a 50-50 proposition in the most optimistic vacuum. It’s more like 10-90.

The Lakers didn’t do anything easy this season, enduring a ridiculous loss to Cleveland before the All-Star break and completing a five-game losing streak the week before the playoffs began.

Still, nobody would have predicted that three Dallas backups (Jason Terry, Jose Barea and Peja Stojakovic) would outscore them in a playoff game, but it almost happened. The backups had 75 points, 11 fewer than the entire Lakers team.

Bryant said he was “very surprised” by the severity of the Lakers’ problems against Dallas.

The off-season could be even more surprising, in many ways.

Photos: Mavericks sweep Lakers

mike.bresnahan@latimes.com

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