The Washington Redskins dropped to 2-5 after a frustrating defeat on the road to the Denver Broncos. Washington kept themselves in the game throughout the majority of it, but fell apart in the fourth quarter.

For me, one of the key moments  came in the fourth quarter. At 21-21, Washington had the ball. On first down, the Redskins ran a play-action pass that got wide receiver Joshua Morgan open down the middle of the field. Robert Griffin III threw the ball slightly behind Morgan, who couldn’t make the adjustment. It fell incomplete. Washington ran two more pass plays that they failed to connect on, before having to punt the ball away. The very next play, Peyton Manning throws a screen pass to Knowshon Moreno, who takes it all the way for a touchdown. Washington was suddenly down, 28-21, and had given up 21 unanswered points. The Redskins never recovered.

Why do I think that was a key moment, with so much time left in the game? Well first, let’s look back to last season, where we saw Washington establish one of its favorite and most effective play-action pass concepts.

After a healthy dose of running the ball, Kyle Shanahan would call for this play-action concept. One receiver, in this case Pierre Garcon, would run a “Go” route to clear away space underneath him. Then the receiver on the other side of the field, Leonard Hankerson here, is able to run a deep crossing route in behind Garcon.

The Giants were so concerned with the run, that they brought a safety into the box, leaving one deep to cover the middle of the field. He has to stay deeper than the deepest, and follows Garcon’s clearing route. Hankerson begins to cut inside.

The linebackers are late to drop back after biting on play-action. With the deep defenders staying back to cover Garcon, Hankerson has a clear gap between zones to run into.

That concept was a staple in Washington’s offense all of last season. They liked to run it out of all sorts of formations and mix in plenty of backfield action as distractions for the defense. It became extremely effective.

Fast forward to this past Sunday, when Washington faced the 32nd-ranked pass defense in Denver. Kyle Shanahan wanted to attack the Broncos’ secondary and went back to one of his best concepts from last year.

Look familiar? This time Aldrick Robinson runs the clearing route deep, while Garcon crosses underneath.

But this time, the deep safety knows what’s coming. Last year, the deep safety was always so concerned with the clearing route that they left the space underneath vacant. But Denver’s safeties weren’t to be fooled quite so easily.

With his first read covered, Griffin is forced to throw it deep in hope that Robinson can run past his defender. But Robinson is well covered and the ball sails 10 yards over his head.

Washington went back to the drawing board and decided to add some window dressing to the same concept.

This time, Washington stacks two receivers on one side of the field. Garcon will run the clearing route up the sideline, while versatile rookie tight end Jordan Reed will run the deep crosser.

But Denver’s safeties see right through the disguise, and both are in position to crash down on Reed’s crosser. Griffin ends up scrambling and then unwisely puts the ball in the air trying to find Hankerson. He was lucky not to be intercepted.

The Broncos just weren’t biting. So Shanahan and his offense set themselves up for another shot. One of Washington’s more effective running plays this season has been the counter. They’ve found particular success when they motion wide receiver Joshua Morgan tight into the formation to run it.

Here, Morgan and tight end Logan Paulsen will cut off the backside of the Denver defense while the rest of the offensive line down block to the opposite side.

As Alfred Morris takes the hand-off, the play looks like a run to the right, but he’s actually going to cut the ball all the way back across the offensive line.

Morgan is able to get out to the second level and cut off a defender from making a play on Morris. That clears a running lane for Morris, who takes on a safety one-on-one. This leads to a 14-yard gain which took Washington inside the 5-yard line. They scored on the next play.

Every time Morgan motioned into that look, Washington ran a counter. Eventually, Denver caught on.

Denver began to bring a safety down into the box to help against the run. That’s when Shanahan once again called for the same concept we saw earlier.

Denver wasn’t expecting the play-action. The deep safety that had been crashing on the underneath route reverts back to his instincts to stay deeper than the deepest receiver. He rotates over the top and stays back to cover the threat of Garcon running deep. That opens up the same lane for Morgan that we saw Hankerson have in the play above.

But the pass from Griffin was slightly behind Morgan. Morgan attempted to make a one-handed grab behind him, but the ball bounced off his hand and fell incomplete.

For me, that was a key moment in the game. They finally had managed to catch Denver off guard and couldn’t execute. With the score tied at 21 entering the fourth quarter, who knows how the momentum gained from that play could have affected the outcome. But Denver was let off the hook. They were able to recover and went back to taking away the underneath route on play-action, forcing Griffin to launch it deep and hope his receiver could beat his defender and come up with it. Griffin was unable to connect on any of Washington’s deep shots and Denver quickly built up an unassailable lead.

Mark Bullock is The Insider’s Outsider, sharing his impressions of the Redskins’ play without the benefit of access to the team.

What’s ahead:

● The Redskins resume practice at 1 p.m., preparing for Sunday’s home game against the San Diego Chargers.

● Mike Shanahan, Robert Griffin III and others speak to reporters today.

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