Former USC star Matt Leinart is released by the Arizona Cardinals

With the start of a new NFL season fast approaching, Matt Leinart headed back home to Southern California this weekend, a quarterback without a team.

The former USC star and Heisman Trophy winner was released by the Arizona Cardinals on Saturday, the latest twist in a roller-coaster career marked by reports of Hollywood parties and unmet expectations.

“I think that in the end we both agreed this was probably the best thing for him, to have a fresh start,” Arizona Coach Ken Whisenhunt said.

Asked about cutting loose the 10th pick of the 2006 NFL draft after four seasons, Whisenhunt said: “I never looked at Matt based on where he was drafted.”

Leinart could not be reached for comment.

“He’s flying home to L.A.,” his agent, Chuck Price, said. “We’re going to see where his next team is.”

The Cardinals spent last week shopping Leinart around the league but could not reach a deal.

Seattle has featured prominently in talk of a landing spot — former USC coach Pete Carroll cut J.P. Losman on Saturday, leaving only two quarterbacks on the roster. The Houston Texans and San Francisco 49ers also have been mentioned as possibilities.

“I have a lot of respect for Matt, and I do believe he can play in this league,” Whisenhunt said, adding: “I think you see a young man that wants to be good, wants to play.”

But Saturday’s roster move stands in marked contrast to the days when Leinart emerged as a marquee passer at USC.

Rewind to 2004-05, to that Heisman followed by five touchdown passes to defeat Oklahoma for the national championship. Only a junior, Leinart might have jumped to the NFL but needed elbow surgery and decided to stick around.

The following season, he led the Trojans back to the title game — they lost to Texas — and subsequently joined the Cardinals, whose then-coach Dennis Green referred to him as “a gift from heaven.”

At that point, his career trajectory began to wobble.

A starter for much of his rookie season, Leinart threw for 2,547 yards but had 12 interceptions against 11 touchdown passes. The next fall, a broken collarbone sidelined him and allowed veteran Kurt Warner to assume control.

There was another important development in Arizona: Whisenhunt took over.

The old-school coach never seemed to mesh with the laid-back California kid and certainly could not have appreciated the blogs tying Leinart to Paris Hilton or Internet photos of him doing beer bongs with college girls. Even when Leinart rededicated himself to the game, getting in better shape, there reportedly was friction.

“When you enter the league with a certain perception, people will continue to believe that perception no matter what you do,” said Steve Clarkson, a private quarterback guru and friend. “It’s unfortunate.”

This season was supposed to offer a second chance, with Warner retired and the Cardinals needing a new leader.

Leinart entered training camp at No. 1 on the depth chart but, as the weeks passed, appeared only sparingly in the preseason.

His numbers were mixed, a 78% completion rate bolstered by short passes, nothing spectacular. Whisenhunt demoted him in late August, handing the spot to Derek Anderson.

Asked what he was looking for with the change, the coach said: “First downs.”

Leinart, meanwhile, seemed mystified.

“I don’t really know what else I could possibly do,” he told reporters. “It probably goes beyond football, beyond the field, actually. For me, I am not making excuses. I am not going to complain. For me, I just really want an explanation and I haven’t been given one.”

Now he’ll have to look for his second chance in another city.

david.wharton@latimes.com

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