Discharged in 1954, Davis got his first job in the pros, as a scout for Weeb Eubank, coach of the Baltimore Colts. A year later, Davis was the line coach and chief recruiter for the Citadel military college in South Carolina, where he spent two seasons.

In 1957 he was hired to coach the offensive line at USC, which was on probation for recruiting violations and slogged through a 1-9 season. Davis persuaded Trojans Coach Don Clark to implement a new blocking scheme that a former player later described as "a kind of hit-'em-and-then-hit-'em-again double block." Davis and others were credited for turning around the Trojans, who went 8-2 in 1959.

But when Clark retired and Davis was passed over to replace him — a fellow assistant, John McKay, got the job — he headed back to the pros and took over as offensive-end coach for the Los Angeles Chargers, a first-year AFL team. He learned under the tutelage of Gillman, who entrusted him with recruiting players away from the established NFL. That was Davis' specialty.

Over three seasons — including a relocation to San Diego — Gillman and Davis helped lead the Chargers to the top of the AFL and created a passing offense that gave opposing defenses fits. It was clear that Davis was headed for even bigger things. Gillman said of his young assistant: "There isn't a doubt in Al Davis' mind that right now he's the smartest guy in the game. He isn't, but he will be pretty damned soon."

Davis made a splash when he came to the Raiders as head coach in 1963, but he was headed for even greater challenges. In April 1966, Davis took over as commissioner of the fledgling AFL, which was overshadowed by the 47-year-old NFL and its popular commissioner, Pete Rozelle.

With his ability to recruit players, Davis weakened the NFL by luring away disgruntled star quarterbacks. Just eight weeks into the job, he signed quarterbacks John Brodie and Roman Gabriel, and other players. The NFL soon agreed to a merger.

Passed over in favor of Rozelle as the new commissioner of the NFL, Davis returned to the Raiders as managing general partner with a 10% share of the franchise. It reportedly cost him $18,500 — a phenomenal investment considering the latest Forbes magazine rankings had the Raiders valued at $761 million. By the mid-1970s, Davis had acquired full control of the franchise, although he never owned all of it. Many individuals own part of the Raiders, but they always entrusted Davis to run the team.

"The things that people criticize him for were probably also the things they should praise him for," said Hall of Fame Coach John Madden, whom Davis hired in 1969 to coach the Raiders.

"Al has his own ideas, and many of them are contrarian," Madden said. "When people said, 'Let's do it the way we've always done it,' Al would say, 'Hey, wait a minute, let's look at this. Maybe there's another way.'"

By the end of the 1980 season, the Raiders were two-time Super Bowl champions and one of the NFL's most popular teams. Despite a decade of sellout seasons in Oakland, however, Davis could not persuade the city to make major improvements to the Oakland-Alameda County Coliseum.

Arguing that his team needed better digs — and the franchise needed the extra revenue to remain competitive — Davis signed an agreement with the Los Angeles Memorial Coliseum in March 1980. For a team to relocate, the NFL requires a three-quarters vote from its ownership, so when Davis tried to move to L.A. without that, he was forced by a court injunction back to Oakland.

In 1982, after a lengthy federal court battle, a U.S. District Court jury unanimously ruled for the Raiders and against the NFL on antitrust and bad-faith counts. Two months later, Davis announced he had signed a 10-year deal with five successive three-year renewal options to play at the L.A. Coliseum.

The Raiders played their first game in Los Angeles in August 1982 and the following season won their third Super Bowl. Tens of millions of viewers watched as Rozelle and Davis — bitter adversaries in the courtroom — shook hands in the locker room after the game.

Throughout the 1970s and '80s, Davis' Raiders provided the NFL with some of its most colorful characters, players such as quarterback Ken "The Snake" Stabler, linebacker Ted "The Mad Stork" Hendricks and cornerback Lester Hayes, who would smear his hands and forearms with Stickum before every game.

Davis later said he didn't realize the extent of his players' involvement with drugs and alcohol. They included defensive end Lyle Alzado, who admitted to having used human-growth hormone and later died of cancer; defensive back Stacey Toran, who had a high blood-alcohol level when he was killed in a car crash; and defensive end John Matuszak, who died of an overdose of Darvocet, a prescription painkiller. When he became aware of the problems, Davis took steps to deal with the problem, including assigning an assistant coach to monitor off-field activity.

Although the Raiders enjoyed some success in Los Angeles, highlighted by their 38-9 victory over the Washington Redskins in Super Bowl XVIII after the 1983 season, Davis was never satisfied playing at the L.A. Coliseum. The stadium had history, dating to the 1932 Olympics, but it lacked luxury boxes, and the team seldom filled the 92,000-seat venue.

Impatient with the Coliseum Commission's promised renovations, Davis shopped around for a new stadium site. In 1987 he announced plans to move to Irwindale and got a $10-million advance from the city. The deal ultimately collapsed and the Raiders kept the money.

By 1995 Davis had shifted his sights to Hollywood Park, where a $250-million privately financed stadium was to be built. However, the Raiders balked when the league stipulated that they would have to temporarily share the stadium with another NFL franchise in exchange for the right to host two future Super Bowls. Davis unexpectedly moved the team back to Oakland, saying there were no "adequate and already existing" stadiums in Los Angeles.

The NFL said the Raiders abandoned Los Angeles simply because they thought they had found a better deal in Oakland; Davis claimed the league forced him to retreat to Northern California by interfering with his attempt to secure a modern stadium with luxury boxes and other amenities.

He insisted the Raiders retained the territorial rights to the nation's second-largest TV market and, if the league tried to place another team in Los Angeles, it would have to buy the rights back from the Raiders.