Last August, David Amerson stood with his family, saying nothing after one of the worst games of his career. Opponents hadn’t just figured out the young cornerback’s weaknesses; they were now targeting him.

A college player’s reputation and NFL draft stock are built on small moments, and those moments come from games, good and bad. How much would a game like this — Tennessee picked on Amerson throughout its 35-21 win over North Carolina State to start the 2012 season — hurt Amerson’s future?

Efland Amerson, the player’s father, stood there with his arms around his son, a junior who was thought to be N.C. State’s best defender. A Navy psychologist, Efland told David that perhaps he could benefit from this. As he had told him often in recent years, it was all in how he looked at it.

“He didn’t say anything for about five minutes,” Efland said this week. “I could feel his body trembling. David has never really failed at anything.”

Eight months later, David became the Washington Redskins’ top draft pick in April, selected with the 19th pick of the second round. He earned his name in college as a defensive back willing to gamble, who could jump routes. In 2011, he set school and ACC single-season records with 13 interceptions. Then in 2012, he gave much of it back as teams took advantage of his tendency to try for big plays rather than staying with assignments. Tennessee’s offensive plan last August clearly targeted Amerson, and Miami went after him later in another N.C. State loss.

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“It wasn’t so much [that] I gave up two touchdowns. It wasn’t that guys were just straight-up beating me,” the 6-foot-3, 194-pound rookie said this week. “It was more that I was beating myself.”

His father, who divorced Amerson’s mother, Tawanna Taylor, years earlier, spent much of his son’s youth overseas on work assignments. Efland’s training is child psychology and pathology, including mental illnesses. It’s an odd thing reappearing in a son’s life and, regardless of his degrees and commendations in the field of neuropsychology, trying to tell him how to handle success and adversity.

So they established trust simply, going trout fishing and having dinner after games. Sometimes they simply caught up on lost time. Other times, David would tell his dad about his goal of playing in the NFL. Efland talked with his son about balance, a word he used with clients in the Navy — he’s finishing a fellowship in Charlottesville — and those from his private practice. Efland said that during his son’s breakout season in 2011, he still explained to his son that extremes are mirages; the tide, no matter how high, always recedes.

Sure enough, a year later, difficulties found David. But rather than trying to analyze his son, Efland tried only to offer fatherly guidance.

“The relationship would change if I start to find myself going into a therapeutic mode,” said Efland, 49. “That kind of naturally happens to me to a certain extent: ‘How are you feeling with this. How are you feeling with that?’

“He’s not dealing with pathology; these are growing pains.”

By the time David’s junior season ended, he totaled five interceptions — solid by usual measures — but he had drawn the reputation of a high-risk player who might pick off a pass but could get burned for a touchdown if he guessed wrong. Regardless, he contacted his father shortly after N.C. State’s final game.

“Pops,” Efland remembers his son saying, “the time is right.”

So David spent the first months of 2013 working to get faster and stronger, but mostly he dedicated himself to fundamentals: footwork and staying true to coverages.

“I was playing the wrong way,” he said of his final season with the Wolfpack. “I was always trying to get interceptions. I wasn’t playing honest as a DB; instead of playing off reaction and reading things and staying fundamentally sound, I started thinking like I know what’s coming every time.”

Amerson, an all-American after the 2011 season who likely would have been a first-round pick if he had been draft-eligible, instead slid to the second round in April.

Raheem Morris, the Redskins’ defensive backs coach, said he wants Amerson to improve his fundamentals — but not at the risk of the instincts that propelled the youngster in 2011 and hindered him a year later. It’s that drive for the big play that the Redskins like so much about Amerson, even if it needs to be sharpened.

“That’s what you’ve got to do at corner. Corners are going to get beat, or they’re going to try to win football games. That’s the name of the game for those guys,” Morris said. “They’re going to get you sometimes, and it’ll be nice to get them back.”

In other words, the Redskins, like Amerson’s father, want the rookie to learn balance, too. And if he reduces his mistakes, he could become a reliable, big-play threat in the secondary. His dad already believes David is a good man, strong and humble, eager to prove himself at football’s highest level.

For his part, Amerson said, his father’s words about extremes and balance make more sense; without spending time at the far ends of success and failure, he believes he wouldn’t be so prepared for challenges he’ll face as an NFL rookie.

“I learned from it,” Amerson said. “Whatever it was, to humble me, to get me back to playing the right way, get me back focused or staying on the task at hand — I just took that whole season, or especially those two games I had, and just learned.”