No matter how Sam Bradford performs over the final five games of the season, the Eagles will have to make a franchise-altering decision at the quarterback position next offseason.

It is a decision that will have far greater repercussions than anything having to do with the head coach. In today's NFL you need a quarterback of certain proficiency if you are to have any chance of winning a championship.

It doesn't matter if Bill Belichick or Chip Kelly is your coach, if you have neither a Hall of Fame-caliber quarterback and an above-average defense nor a quarterback a notch or two below and a once-in-an-era defense, your chances of snaring a title are virtually nil.

This isn't rocket science. Every team knows as much. But year after year, teams fail to construct the formula, mostly because there are only so many quarterbacks capable of playing at the requisite level for winning in the postseason.

Kelly has opened his three seasons with a different starting quarterback, and each time - presuming they don't win a Super Bowl this year - the Eagles have fallen short. But does that mean he isn't capable of selecting the next quarterback - whether it is extending Bradford or finding one via the draft, free agency, or trade?

The choices made at quarterback during that span can't all be placed on Kelly's shoulders. Then-general manager Howie Roseman had final say in the 2013-14 offseasons.

But decisions on free agents weren't made unless both agreed on the player, according to sources familiar with their working relationship. Perhaps one had to be convinced more than the other, but if there was a strong difference of opinion, they simply moved on.

Michael Vick was under contract when Kelly was hired, but none of his remaining salary was guaranteed. The Eagles had no obligation to keep him. But they restructured his deal and gave him what was essentially a one-year commitment.

Kelly said at the time that Vick would compete with the returning Nick Foles, who was entering the second year of his rookie contract. There weren't many attractive quarterback options that offseason, although it should be noted that the Cardinals and Chiefs traded for Carson Palmer and Alex Smith, respectively, after the Eagles had settled on Vick and Foles.

The Eagles avoided expending high picks on either E.J. Manuel or Geno Smith in a quarterback-weak draft, but they did trade up for Matt Barkley in the fourth round. Kelly was the driving force behind the Barkley pick. After two seasons as the third-stringer, Barkley was traded to Arizona in September.

Kelly won 10 games and the NFC East title with Vick and then Foles. Foles had a statistically excellent season (27 touchdowns and only two interceptions), but he started in only 10 games, and after a first-round playoff loss, Kelly hedged on giving him an endorsement for the next season.

However, by that February, Roseman said Foles would be the returning starter. A few weeks later, the Eagles signed Mark Sanchez to be the backup. They not only made their opinion of Barkley clear with this move, but it likely took them out of the running for a one of three quarterbacks who were projected to be on the board when they drafted in the first round.

The Eagles passed on Johnny Manziel in the draft and traded back to take linebacker Marcus Smith with the 26th overall selection. Teddy Bridgewater and Derek Carr were taken six and 10 picks later, respectively. While the jury is still out on either being good enough to be included in the Super Bowl-winning categories, Carr appears to have the potential.

Foles' play regressed in 2014. Sanchez was inconsistent. Kelly still won 10 games but failed to make the playoffs. He was given full control over personnel in January as Roseman was ushered out. From that point forward, every quarterback decision made was Kelly's.

He dealt Foles and a second-round pick to the Rams for Bradford, while also trading away Foles' $660,000 salary for Bradford's $12.9 million one. Neither quarterback has played particularly well this season. Foles was eventually benched, however,and Bradford, who is in the last season of his contract, showed marginal improvement before missing two games because of injury.

But the price the Eagles gave up for Bradford - a second-rounder seemed exorbitant even at the time - becomes increasingly steeper with each game they lose. Kelly also re-signed Sanchez to a two-year deal.

While he was hardly the lone reason the Eagles lost their last two games by a combined 59 points, his performance didn't justify Kelly's faith. Even before the Eagles had dealt for Bradford, Kelly had told other NFL evaluators that he could win with Sanchez, according to sources familiar with the conversations.

The only other significant quarterback acquisition Kelly made this offseason was signing Tim Tebow. There was an NFL Network report that free-agent Tyrod Taylor had wanted to play for the Eagles. Whether Kelly had interest or not, the Bills signed Taylor to a three-year deal worth only $3.35 million on March 12.

Tebow worked out for the Eagles on March 16 and signed a month later. He was released on the same day Barkley was traded. Taylor is now starting for the Bills.

Kelly flirted with the idea of trading up for Marcus Mariota in the draft, but ultimately he decided that the price was either too steep or that the Titans weren't interested in trading away the second overall pick.

In retrospect, Kelly probably should have meet Tennessee's pre-draft demands, however outrageous. There will be options this offseason - Trade for Colin Kaepernick or Robert Griffin III? Draft Jared Goff, Paxton Lynch, Connor Cook, or fill in the blank? Bring back Bradford? - but will any be as attractive?

And can Kelly be trusted to pick the right guy? His track record is mixed. But so are those of the many general managers who were never able to get one of the few difference-making quarterbacks.