“If you take a quarterback with the No. 1 pick — with history showing that it’s at best a coin flip? If you’re Detroit, can you survive [his failure]?” he says. ”It’s silly to think that [the pick] can be done in a vacuum and not take into account where the Lions are right now. It’s a very intriguing pick.”

Mistakes at quarterback happen, Casserley said, when, “you force the need up on the board. [With Carr], we felt, ‘If we don’t take the quarterback now, we’re not gonna get one,’ and we needed to get started building the team.”

Mark Jackson was the Raiders' Director of Football Development in 2007 when they selected Russell, a two-year starter for LSU who threw for more than 5,000 yards and 41 touchdowns. Big and blessed with a strong arm, Russell wowed scouts with his physical gifts.

But it was his pre-draft preparation that sealed him as a No. 1 selection, which can be part of the problem.

“These kids are so well-trained to say and do all the right things,” Jackson says “To get a sense of who they are, you either have to live with them and or go back to before they were on anybody’s radar. From the time they declare for the draft, they are so well-prepared and in the best shape of their lives. They’re sharpened for interviews, all their bases are covered.”

This preparation can, in part, undermine the legwork done by NFL scouting departments. These scouting departments — with the general manager normally at the top of the flow chart — usually employ between 15 and 20 people. From the entry-level scouting assistants to area scouts and national scouts up to the directors of college personnel, all have a voice in the process. And all 20 pairs of eyes are on the hundreds of players coming out each year with special attention paid to those players in the top 100 or so prospects.

After spending all that time spent scouting and interviewing the prospect, teams don’t have many doubts when it’s time to actually make the selection.

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“You feel secure it’s a can’t-miss," Jackson said. “You’ve heard the dissenting voices and you have listened to them. You’ve done the research and done it ad nauseum and you know that this guy will perform in the league. It’s hard to find a guy that people said the day he was drafted, ‘God, they really reached. That’s really a big gamble.’ ”

To that point, Billick brings up Ryan Leaf. He was the No. 2 pick in 1998, some thought he would be a better pro than Peyton Manning, who went No. 1 that year. Leaf was a disaster on the field and off and out of the league by 2001.

“San Diego gets saddled with that debacle, but if it hadn’t been San Diego, the teams at three, four, five or six would have taken him,” Billick said.

The siren song of the franchise quarterback is a powerful draw, said Chargers General Manager A.J. Smith.

”You can have great offensive players, a great defense, great special teams and be so proud of everybody,” he said. “If you don’t have a quarterback, you’re done, thanks for coming. That’s the reality you’re under. You must have a quarterback to take you over the hump.”

Sometimes, the team picking No. 1 has to show some guts.

In 2004, Smith and the Chargers held the No. 1 pick. He selected Eli Manning even as Manning’s family and advisors warned Smith that Manning didn’t want to play for San Diego. It was a bold move that could have backfired. But Smith made it work, trading Manning to New York.

In exchange, the Chargers wound up with quarterback Philip Rivers, linebacker Shawne Merriman and kicker Nate Kaeding. All have been Pro Bowl performers.

“If there’s a question about the ability of the player you’re taking, you need another football player,” Smith said. “There’s a lot of talk about the pressure of picking No. 1 like it’s the ultimate weight-bearing pressure a person can be under. Just get it right. Get it right.”

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