It's a steep drop to backup QB

Fans in football cities love the backup quarterback. NFL coaches simply cross their fingers at thought of using one.

While fans might call for the next guy to go in and show his skills, coaches worry. They should. The long-standing belief around the league is that a good backup quarterback can come off the bench and win three games, but if that quarterback plays six games, he'll lose three of them.

Advanced statistics back up that theory. I'd have faith that Matt Hasselbeck, Matt Moore, Shaun Hill and a few other backups can do that and more. What I don't see is many other backup options to take a team 3-3 over a six-game span.

Coaches who have mobile, read-option quarterbacks should take note. The drop-off from the starting quarterback to the backup is vast, and the fall can be dangerous.

After Michael Vick was sidelined in Philadelphia last season, Nick Foles went 1-5. Brady Quinn was 1-7 as a replacement for Matt Cassel in Kansas City. Chad Henne was 1-5 replacing Blaine Gabbert. Hasselbeck went 2-3 for the Tennessee Titans filling in for Jake Locker. Kevin Kolb almost fulfilled the backup quarterback profile by winning his first three starts as a backup for the Arizona Cardinals. But he lost the next two and then lost his job.

League-wide, backups went 12-37 last season. Ouch.

The numbers bear out the drop-off from starter to backup -- and why coaches should worry. Projected starters for this season averaged 24.2 points per game during their careers. Projected backups have a career average of 19.5 points per game.

When you consider that, on average, it takes more than 21 points per game for a team to be the winner, the 4.7 point drop in scoring puts a team in position to lose.

Analytical stats provide more support for the drop-off theory. ESPN Stats & Information evaluates every throw made by a quarterback and gives it a QBR rating. Pro Bowl quarterbacks score in the 70s. Average starting quarterbacks score around 50. Those quarterbacks who would project more losses than wins are below 50.

A majority of the backups have ratings in the 20s, 30s and 40s.

Thanks to increased pass-oriented offenses in the college game, the NFL is in a better position to develop starting quarterbacks. Thanks to the development of Matt Ryan, Joe Flacco, Cam Newton, Andrew Luck, Russell Wilson, Colin Kaepernick, Robert Griffin III and others, more teams have good quarterbacks than at any time I can remember.

But the NFL still isn't developing enough quarterbacks, and you can see it in the backup ranks. The backup position can be categorized in three ways -- solid backups, failed starters and possible quarterbacks of the future.

The solid backup list is headed by Kyle Orton, Hill, Jason Campbell, Moore and T.J. Yates of the Houston Texans, who did a nice job filling in for Matt Schaub two seasons ago. Hill, for example, has averaged 22.4 points a game in the 26 times he's started.

Hasselbeck, Cassel and Ryan Fitzpatrick have moved over from starting roles and should be good backups. Any one of those eight quarterbacks could come off the bench and help a team get to a three-game winning streak.

When you start to get into the failed-starter area, a lot of questions evolve. The Seattle Seahawks knew it was going to be tough to keep Matt Flynn as Wilson's backup on a three-year, $19.5 million contract, so they traded him to the Oakland Raiders to be the starter. They signed Quinn as a backup. Wilson averaged 25.9 points a game as a starter. During Quinn's 20 career starts, he averaged 15 points and has a 4-16 record.

A 10.9-points-per-game drop could turn an 11-win Seahawks team into a .500 team unless Seattle wins on defense. The Seahawks gave up 16.2 points per game on defense last season.

Other failed starters create more challenges for franchises. Henne didn't work out in Miami and struggled in Jacksonville last season. In his 37 career starts, he's averaged 19.5 points a game. His record as a starter is 14-23.

The 49ers traded Alex Smith to Kansas City and brought in Colt McCoy as the backup. Kaepernick helped to carry the 49ers to the Super Bowl last season. He averaged 26.3 points a game during his seven regular-season starts and 34.7 points a game in his three playoff games. McCoy brings a 15.6-points-per-game average to the 49ers from Cleveland.

This final group of backups is still waiting for playing time. The Patriots have the strong-armed Ryan Mallett, but he hasn't played because of Tom Brady's durability. The Denver Broncos are developing Brock Osweiler behind Peyton Manning. Kirk Cousins offers a lot of promise behind RG III but has only has one regular-season start.

The read-option is creating a lot of excitement and creativity among coaches, but teams had better watch out. If a good starter can anticipate getting 24 points and the backup is going to come off the bench and score less than 20, starting quarterback preservation should be taken into account.