LANDOVER, Md. - The Eagles need a starting quarterback.

It won't be Mark Sanchez.

That realization came long before the Eagles' playoff-dashing loss to the Redskins on Saturday. But it was hammered home when Sanchez, given the opportunity to lead his team on a game-winning drive, threw another interception.

It was his 13th turnover in a little more than 71/2 games. That's about par for his course. Sanchez had 98 turnovers in 62 games in his previous life as a New York Jets quarterback. He is what he is, and that is a decent backup. But he is not a reliable long-term starter.

Nick Foles was supposed to be that guy, or at least have a chance to be that guy. But he had the same number of turnovers in a little less than 71/2 games this season.

Foles does have the 2013 season, in which he committed just three turnovers in 10 starts, on his resume. That should be enough for the Eagles to bring him back next season, not to mention his third-round rookie contract (read: cheap).

But getting a quarterback, even if it ultimately proves fruitless, should be priority No. 1 for Eagles coach Chip Kelly this offseason. The Eagles have several other holes, and they were aired like dirty laundry for the NFL to see Saturday. But the quarterback situation isn't going away.

It's time to knock down a few myths: Kelly's offense doesn't magically turn quarterbacks into future Hall of Famers. The newness of his scheme caught defensive coordinators off-guard last season, and that certainly contributed to Foles' 27-touchdown, two-interception run.

But Kelly - and he probably would be the first to admit this - needs the same things from his quarterback that all coaches need: a quick decision-maker who can read defenses and has the arm to make all the necessary and accurate throws from the pocket. If he can run, so be it.

There aren't many great ones out there. Sanchez was ultimately just a backup playing on a one-year deal. He won three of his first four starts, including coming off the bench for the injured Foles and guiding the Eagles past the Texans. But he now has lost three in a row, and with Foles still unlikely to be cleared next week, there could be a fourth - with the Eagles slip-sliding away.

"You've got to win games," Sanchez said. "The head coach and the quarterback - we're the only ones who keep a record, so it goes with the territory of this position. There have been three really tough games, and this one came down to the wire and we came up a little short."

With the score knotted, 24-24, the Eagles took possession at their own 15 with 2 minutes, 36 seconds remaining. Sanchez completed five passes on the first six plays to move the Eagles to the Redskins 48 with 1:36 left.

But the Sanchez who had been dormant for more than three quarters reappeared. He dropped on third and 4 and the Redskins blitzed. Jeremy Maclin had cornerback Bashaud Breeland on him, but he had space.

Sanchez simply threw low, behind his receiver, and Breeland picked it off.

"We got an all-out pressure, and I was trying to buy a little time and anticipate where Mac was going to be," Sanchez said, "and I just kind of missed it."

Maclin, who caught four passes for 62 yards, said he thought he had Breeland beaten.

"It was a tough route for what coverage they had," Maclin said. "But the ball was behind me."

It was the third consecutive game in which Sanchez threw a fourth-quarter interception. He also threw a pick on the last play of the third quarter in last week's loss to the Dallas Cowboys. He has 10 interceptions this season and three fumbles, including the one he gave up on a first quarter strip-sack by Redskins linebacker Ryan Kerrigan.

In between the two turnovers, Sanchez did some of his best work. Overall, he completed 37 of 50 passes for 374 yards and two touchdown passes to Riley Cooper. But the interception will and should be all that anyone remembers about his game.

"The guy made an unbelievable play," Sanchez said. "It would have been a great throwaway and we get a fourth down and we're still rolling. So it's really too bad."

The Redskins scored the winning field goal off the pick. They netted three points off the fumble, too.

As much damage as he did in between the turnovers, Sanchez also missed some opportunities. He moved the Eagles to the Redskins 8 midway through the fourth. After LeSean McCoy was held to no gain on first and goal, Sanchez checked down to Zach Ertz for 4 yards.

On third down, he went back to his tight end.

"I tried squeezing it into Ertz," Sanchez said. "They ended up dropping eight, so I was just trying to get a quick one over the middle. They converged on him pretty quick."

Ertz got one hand on the ball, but it would have been a difficult catch.

"I'm the No. 1 option on that, and if everyone closes on me, it may be worth [going to] another guy," said Ertz, who set a franchise record with 15 catches. "But I've got to make the catch."

For the fourth straight game, Sanchez hardly threw deep. Kelly said the Redskins were playing a deep zone.

"There were chances," Maclin said, "that we could have hit the ball down the field."

Foles takes those chances. With the playoffs all but out of reach, the Eagles won't likely get an opportunity to see him throw until next season.

He may be all they've got.

jmclane@phillynews.com

@Jeff_McLane