Enlarge By Denis Poroy, AP Former Chargers receiver Lance Alworth said the team's rivalry with the Raiders flared up after Al Davis left San Diego to run the Oakland franchise when both were in the AFL. "He would give us heck every time we played," Alworth said.  ABOUT THE AFL SERIES USA TODAY will celebrate the American Football League's 50th anniversary this summer with a series of retrospectives.  THE AFL, 50 YEARS LATER Photos: Key moments and decision makers from the AFL's impactful tenure Upstart to the big time: How the underdog AFL changed the course of the NFL Patriots: Nomad team had humble beginning before reign as NFL champs Dolphins: After slow start in the AFL, Shula-led Dolphins flourished Bengals: AFL's Bengals became Paul Brown's entry back into NFL Broncos: Couldn't put a sock in 'second-class' days in AFL Raiders: Lamonica's Raiders took pride in wide-open offenses of AFL Chiefs: After they left Dallas, the Chiefs became the toast of the AFL Jets: Broadway Joe's win in Super Bowl III etched league's place in lore Bills: AFL glory days came too early for Bills to make a Super mark Oilers: Team owner Bud Adams' influence often overlooked

Under innovative head coach Sid Gillman and a staff that included Chuck Noll, Bum Phillips and, perhaps most telling, Al Davis, San Diego featured a new breed of passing attack that was unheard of in the pre-Kennedy era. Gillman, who coached the NFL's Los Angeles Rams, ran what Hall of Fame receiver Lance Alworth calls "the original West Coast offense."

Alworth was the Chargers' biggest name. He led the AFL in receiving yards and receptions three times each and remains the franchise's all-time leader with 9,584 receiving yards.

But Gillman had plenty of other talent. Jack Kemp, who would become a star in Buffalo, was the original quarterback before John Hadl took over in 1962. Hadl twice led the AFL in passing, and only Hall of Famer Dan Fouts has surpassed Hadl's 26,938 passing yards and 201 touchdown throws in San Diego.

The backfield also featured Paul Lowe, who led the AFL in rushing in 1965. Hall of Fame tackle Ron Mix anchored a strong offensive line.

"It was the most explosive offense I'd ever seen," Mix said recently from his San Diego law office. "We were doing things that weren't done by other coaches: running halfbacks into pass patterns, using (multi-) receiver (formations), running pitches to the back around end.

"The scheme was aided by tremendous football talent. At any moment, you could expect to see Paul Lowe, Keith Lincoln or Lance Alworth exploding for a touchdown."

That quick-strike approach helped the Chargers to the AFL Championship Game five times between 1960 and 1965. But they walked away with only one title, a 51-10 drubbing of the Boston Patriots in 1963 when San Diego's offense paced the AFL in points scored and yards gained.

Alworth and Mix agree that the defense played by teams such as the Buffalo Bills and Houston Oilers hindered their ability to win numerous titles. Alworth also feels injuries played a major factor in his team's failure to win multiple AFL crowns.

"I had been hurt in the previous game, I found out years later," Alworth says of a knee injury that hampered him in the team's 20-7 loss to the Bills in the 1964 title game. "I had torn an ACL."

Mix has other ideas about why the Oilers bested the Chargers in 1960 and 1961.

"The Houston Oilers had done a great job of putting together a team and had gotten NFL players," Mix says of a club that signed NFL veteran George Blanda as its quarterback and halfback Billy Cannon, winner of the 1959 Heisman Trophy. "They bought the championship."

While the Bills and Oilers gave the Chargers problems in the postseason, their biggest rivals were situated just up the coast in Oakland. Davis' defection to the Raiders in 1963 helped set the stage for a decades-long rivalry.

"Sid Gillman created the rivalry," Mix says. "To Sid, the ultimate act of disloyalty was to leave his coaching staff. ... Before Al got to the Raiders, we used to beat them by 40 points a game. He took great pleasure in turning that around. Not because it was (his former team), but because the Chargers were the gold standard at that time."

Alworth makes it clear that Davis also fueled the rivalry. "He would give us heck every time we played," he says.

But Alworth admits that he owes much of his success to Davis, who recruited him out of Arkansas and converted him from running back to receiver. Alworth calls Davis "a very knowledgeable guy, a great judge of character and athletes."

While the offense got all the attention, Mix says the defense played a huge role in San Diego's success.

"The defense was really overlooked," Mix says of a group that was consistently ranked near the top of the AFL. "Every time (they took the field), it was three-and-out. Chuck Noll, Jack Faulkner and Bum Phillips were outstanding coaches."

But AFL battles aside, Mix admits that the biggest rivalry in those days was with the NFL. He talks about being drafted by the powerful Baltimore Colts and recounts how their offer fell far below San Diego's.

"I told (Colts owner) Carroll Rosenbloom about the Chargers' offer, and he said, 'Go ahead, take it. That league's going to fold anyway.'

"That's how they viewed it. When they lost Joe Namath to the Jets (who outbid the St. Louis Cardinals for the QB), that's when they finally started paying attention."

Both Mix and Alworth got a taste of the NFL after the 1970 merger. Following a brief retirement, Mix received an offer from, of all people, Davis in 1971. He said playing for his longtime rivals was not that difficult. "Guys are the same on every team," says Mix, who started four games in his lone year with Oakland.

Alworth, a Houston native, had a different experience after joining the Dallas Cowboys, also in 1971. Upon arriving, Alworth was brought in to meet with head coach Tom Landry.

"He said, 'Look, the reason I traded for you was to block,' " says Alworth, who averaged 55 receptions per season over his nine years in San Diego but caught 49 balls total in two years with the Cowboys. "He said, 'If you block, we'll win the Super Bowl.'

"And we did."

The Chargers are still awaiting their first Super Bowl title. But San Diego will always retain a championship legacy from its days as an AFL powerhouse.