BALTIMORE MD , August 25 : Washington Redskins quarterback John Beck (12) during the Washington Redskins play the Baltimore Ravens in a NFL preseason game at M&T Bank Stadium in Baltimore MD August 25, 2011. (Photo by John McDonnell/The Washington Post) (John McDonnell/The Washington Post)

Quarterback controversy.

You might hear those two words a lot in the next few days. That’s because the Washington Redskins have one, and that’s not good news.

A quarterback controversy happens when a team can’t decide which of its quarterbacks to play. The Redskins started Rex Grossman the first five games of the season. The team has a good record — three wins and two losses — but Grossman has not played well.

Grossman has thrown six touchdown passes. But he has also thrown nine interceptions, including four in Sunday’s loss to the Philadelphia Eagles. Grossman is ranked 32nd out of 33 NFL quarterbacks.

So the Redskins switched to backup John Beck in the fourth quarter against the Eagles. Head coach Mike Shanahan announced Wednesday that Beck will start against the Carolina Panthers on Sunday.

Changing a quarterback is a big deal. The best teams don’t switch quarterbacks. They have one they can count on. Think of Tom Brady for the New England Patriots, Aaron Rodgers for the Green Bay Packers or Drew Brees for the New Orleans Saints.

This is not the first time the Redskins have had a quarterback controversy. Last year, Shanahan replaced starter and two-time all-pro quarterback Donovan McNabb with Rex Grossman during the last three games.

And if you know any longtime Redskins fans, ask them about Sonny Jurgensen and Billy Kilmer. They were at the center of perhaps the team’s most famous quarterback controversy.

After being terrible for years, the Redskins got much better in the 1970s under head coach George Allen. (By the way, Allen’s son Bruce is now the general manager of the team.)

Even though the team had improved, Washington fans were split about who should start at quarterback. Some fans wanted Coach Allen to play Sonny Jurgensen, while others wanted Billy Kilmer. People even put bumper stickers on their cars that said “I Love Sonny” or “I Love Billy.”

For the most part, Allen started Kilmer, because Jurgensen kept getting injured. Kilmer led the Redskins to Super Bowl VII (that’s the Roman number 7) following the 1972 season; the Redskins lost that game to the Miami Dolphins, 14-7.

The difference between the Jurgensen-Kilmer quarterback controversy and the Grossman-Beck controversy is that both Jurgensen and Kilmer were terrific quarterbacks. Jurgensen, who is now a popular radio and TV announcer for the team, was a fabulous passer who was a five-time all-pro. Kilmer’s passes were wobbly, but he was a fiery leader who was named all-pro twice.

Grossman and Beck are not all-pros. But one of them had better start playing as if he is, or the Redskins might be sunk.

Fred Bowen is the author of 17 sports books for kids. His latest, “Quarterback Season,” was published in August.