Jason Giambi has struck out on another endorsement deal.

Nike (NKE) said yesterday that it opted not to renew the multimillion-dollar deal with the fallen Yankee that expired last month.

That means four of Giambi's five corporate sponsorship deals — worth an estimated $3.5 million of the player's total $4 million in annual endorsement booty — have walked.

The slumping slugger shrugged off Nike's "nay," saying, "My deal was up anyway. It expired."

He also downplayed his other sponsorship losses, insisting, "We decided this year to concentrate on baseball, because a lot of deals require appearances."

Nike did not say whether the decision to drop Giambi from its lineup of All-Star endorsers was due to his poor on-field performance or to him being tainted by the recent steroid controversy.

One thing is for sure — .234 hitters don't typically sell many shoes. The decision by Nike is believed to have cost Giambi about $1 million a year, according to several sports business professionals. Nike refused to comment.

Steve Lauletta, who heads a sports-marketing company, is not surprised by the turn of events.

"Companies choose what players and imagery connects with the fans and which player will help sell product," said Lauletta, who headed Miller Brewing's (search) sports marketing operation. "What is the surprising part is how quickly the on-field falloff has been."

Giambi, a career .295 hitter, is hitting just .234 this season with a team-leading 39 strikeouts. He has four home runs and 13 runs batted in. He hit .208 last year.

The trouble may have started last year, when testimony leaked from a federal grand jury probe into illegal steroid sales named Giambi as someone who used the muscle-builder. For many fans, that news tainted Giambi's image.

UltraMax deodorant, one of the most visible of the Yankee's endorsement deals, didn't renew its estimated $1 million-a-year contract last month.

That decision was made last December, according to ESPN.com, which first reported on Nike's decision yesterday.

Ironically, the TV spots for the deodorant ended with the tag line, "All the muscle a man needs."

Pepsi's two-year deal with Giambi, at a reported $1 million a year, ended last year. Sega Sports (search) also dropped Giambi as the cover boy to its ESPN video game. That deal netted the 34-year-old about $500,000 a year, sources said.

The corporate exodus shows it's a lot easier for Madison Avenue to leave Giambi behind than it is for the Yankees.

The Bronx Bombers still owe Giambi about $80 million from his gigantic seven-year, $120 million contract signed in 2002.

But not every endorse ment is bust. Louisville Slugger (search), which has been with Giambi since he returned to minor league ball from playing on the U.S. Olympic team in 1992, is sticking with him.

The company's four- year deal, at an estimated $500,000 annually, runs through the end of the season.