The most important thing that new Redskins quarterback Mark Sanchez can do is not turn the ball over against the Giants. (Jonathan Newton/The Washington Post)

After losing two quarterbacks in little more than two weeks, the Redskins must find a way to get their season started again. They will do so at home against a team they beat on Oct. 28: The New York Giants. This time, however, it will be a very different Redskins team — one led by Mark Sanchez, not Alex Smith, at quarterback. The Redskins also have lost four starting guards since that day. The Giants are playing better and Washington is tumbling.

Don’t turn the ball over

Fans might have been frustrated with Smith’s hesitation to take big chances with his passes and while this likely kept his passing yardage numbers down, his caution prevented him from making mistakes. A big reason the Redskins were 6-3 before his injury: Their turnover margin was among the best in the league.

One of the biggest criticisms of Sanchez throughout his career is that he has been careless with his throws. This was exposed in Monday’s loss at Philadelphia. After leading Washington on an impressive scoring driving just before halftime, he was intercepted deep in Eagles territory early in the second half. It was a mistake that put the Redskins too far behind to catch up.

Run Adrian Peterson

Each week, the Redskins talk about how they want to get their top running back going, and each week this doesn’t happen. Defenses have stacked the box against Peterson early in games, daring Washington to beat them in the air — something the Redskins have not been able to do. But Peterson remains the team’s best weapon and he needs to be used more.

He says his shoulder separation, reinjured in the last game against New York, is not an impediment. A patched-up offensive line with two new starting guards could make it hard to run, however. Peterson did show he still has a burst with his 90-yard touchdown run against the Eagles, but the fact that he didn’t have a 100-yard rushing game despite that run speaks volumes about the need to get him started.

Stop Saquon Barkley

The Giants’ rookie running back has been phenomenal with 954 yards rushing, 602 receiving yards and 12 total touchdowns. Last time, the Redskins held him to just 38 yards rushing. He has rushed for more than 100 yards in each of the past three weeks and is a huge part of the Giants’ recent revival. (New York has won three of its past four games.)

If Washington can’t stop him early, it could be a long day for the defense.

Tackle

For some reason, Washington’s defensive players seem to have forgotten how to tackle. This is a strange development because this was a huge strength early in the season. But in recent weeks, the team has allowed ball carriers to break away for huge runs both from scrimmage and after the catch.

The Redskins’ coaches don’t seem to have a good answer for what has happened to the tackling. Injuries haven’t decimated the defense the way they have the offense. Players are going for strips too much instead of wrapping up and that probably is a factor. Without better tackling, Washington is going nowhere.

Stick together

One of the team’s strengths has been its cohesion. Players talk about how close they are and how their locker room doesn’t have divisive cliques. But Smith, the quarterback who helped build that bond, is gone, and so too is longtime backup Colt McCoy. The Redskins now are being led by a quarterback who still doesn’t know everybody’s name. Their likely starting guards weren’t with the team a month ago.

So far, the unity seems to have held. Still, so much chaos swirls around this team that the best of bonds can easily fray. Communication has been poor on the defense at times and the makeshift offensive line will likely have trouble adjusting to a third quarterback in three weeks.

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