What happens when one team's backup QB becomes another team's starter?

All eyes will be on Houston this season as critics will see if Brock Osweiler can go from backup to a starter -- who wins -- in one season. AP Photo/Joe Mahoney

HOUSTON -- In signing Brock Osweiler the Houston Texans are trying something several teams have before. They're taking another team's backup quarterback and asking him to lead them.

It's not the first time the Texans have done this. In 2006, Houston traded two second-round picks and swapped first-round picks with the Atlanta Falcons for the Falcons' backup quarterback Matt Schaub, who had started two games in three seasons.

Schaub went 46-42 with 88 starts during his Texans' tenure, according to ESPN Stats & Information. He had a Total QBR better than 60 in five of his seven seasons and was instrumental in the Texans' first two playoff berths in 2011 and 2012. Had he not missed the end of the 2011 season with a significant foot injury, the Texans might have advanced further than they did.

Schaub's ending in Houston turned ugly as his barrage of pick-sixes led to the worst season in Texans' history (2-14). At his peak, he did some good things in Houston. Since his necessary departure, the position has been a disaster for the Texans. They've since made do with a series of former backup quarterbacks who couldn't play up to a starter's level. Houston fully believes Osweiler will be able to step into that starter's role.

This plan has had some failures, but some impressive success stories, too. With the help of ESPN Stats & Info, let's take a look at some.

Matt Cassel

From ESPN Stats & Info: In 2005, the Patriots used a seventh-round pick (230th overall) on USC QB Matt Cassel, who backed up Carson Palmer and Matt Leinart. Cassel neither started any games nor threw more than 10 passes in a game at USC. Cassel has made 79 starts in the NFL (35-44 record), with a 42.6 career Total QBR. Cassel had 39 career pass attempts from 2005-07, but went 10-5 with the Patriots in 2008 after Tom Brady went down in Week 1 with a knee injury. Cassel finished with 21 passing touchdowns and 11 interceptions, finishing eighth in passing yards (3,693). The Chiefs gave the Patriots a 2009 second-round pick in exchange for Cassel and veteran LB Mike Vrabel. Cassel then signed a six-year contract worth $28 million guaranteed shortly after the trade. He went 19-28 in four seasons with the Chiefs and lost his only playoff start in 2010.

My take: The Chiefs reacted to Cassel's starts when Tom Brady was hurt to trust him with their team, and it didn't work out great. Overestimating the ability of a Brady backup is fairly common, but what made Cassel even tougher to predict was that there wasn't any semblance of a college sample to examine.

Matt Flynn

From ESPN Stats & Info: In two starts for the Packers (2010-11), Matt Flynn was 55-81 (67.9 percent) for 731 yards, 9 TDs and 2 INTs (58.6 Total QBR). Flynn turned those two starts into a contract worth $19 million over three years, including $10 million in guaranteed money. Flynn earned $14 million between the Packers and Raiders before being released in October 2013.

My take: While there was an assumption Flynn could be a starter, the Seahawks didn't feel controlled by this move or the contract. He lost the starting job to Russell Wilson, which has worked out pretty well for the Seahawks.

Charlie Whitehurst

From ESPN Stats & Info: In 2010, the Seahawks traded a third-round pick and swapped second-round picks with the Chargers (60th overall for 40th overall) for Whitehurst, who hadn't yet thrown an NFL pass attempt. Whitehurst has made nine starts for two different teams since the trade, posting a 2-7 record and a 27.7 career QBR (all after the trade).

My take: While the Seahawks hoped touchdown Jesus would develop into a franchise quarterback, they weren't married to the idea. They gave him a two-year deal worth $8 million and gave it a shot. Whitehurst never truly developed into that quarterback and is now a backup for the Tennessee Titans.

Matt Hasselbeck

From ESPN Stats & Info: In 2001, the Seahawks traded a third-round pick and swapped first-round picks (10th overall for 17th overall) with the Packers to acquire Hasselbeck. Hasselbeck had made zero starts when he was traded, and threw only 29 passes from 1999-00 as Brett Favre's backup. Hasselbeck started 131 games over the next 10 seasons and is Seattle's all-time leader in completions and yards. Also of note, Seattle's first-round pick after the swap (17th overall) was used to draft five-time All Pro guard Steve Hutchinson.

My take: As we've seen here, the Seahawks have a long tradition of doing this and this was by far their most successful try. The Texans should be delighted if this is what they get from Osweiler. Hasselbeck's got more than a dozen franchise records, and more importantly, the Seahawks earned five consecutive playoff berths and one Super Bowl appearances with Hasselbeck.

Mark Brunell

From ESPN Stats & Info: Mark Brunell threw 27 passes over two seasons in Green Bay while backing up Brett Favre from 1993-94. The Jaguars traded a third-round pick and fifth-round pick in the 1995 draft to acquire Brunell, who is Jacksonville's all-time leader in completions, pass yards, pass TDs and wins.

My take: Another success story here from another player who backed up an all-time great. Brunell led the Jaguars to playoff appearances in three of their first four seasons and once to the AFC Championship Game.

Rob Johnson

From ESPN Stats & Info: Brunell's backup in Jacksonville was Rob Johnson from 1995-97, who made one start in Week 1 of 1997 (20-24, 294 yards, 2 TD) before the Bills traded a first-round pick (which became Fred Taylor) and fourth-round pick for him. Johnson went 9-17 in Buffalo as a starter from 1998-01, while Taylor became the Jaguars' all-time leading rusher.

My take: Worth noting, the Bills also gave Cassel a chance to be their starter.