Video (02:58) : Vikings offensive linesman Brandon Fusco has been sitting out of practice because of a concussion.

Meet Vikings defensive end Justin Trattou, the NFL’s most efficient defender through two weeks of the 2015 season.

Who? And the what?

You know. Justin Trattou. The defender with six snaps, one interception, zero quit.

“He’s kind of one of those guys who grows on you,” coach Mike Zimmer said. “He plays hard. He works.”

By NFL standards, Trattou isn’t much to look at.

“Hey, Jared Allen didn’t have that sculpted look either,” said defensive tackle Sharrif Floyd, who has known Trattou since they played together at Florida. “It doesn’t matter how you look, it’s how you perform. He makes plays because there’s a lot of fight in him.”

Vikings DE Justin Trattou (94) got a rare chance to celebrate after his fourth-quarter interception last Sunday against the Lions.

Trattou isn’t a starter. He isn’t even a second-teamer on the depth chart.

Ask him if he thinks he’ll play Sunday against the Chargers and he can’t tell you. Some weeks, he doesn’t know until the inactives are announced 90 minutes before kickoff.

“I could play 35 plays; I could play five plays,” Trattou said.

Or no plays at all, which he did as an inactive for the season opener at San Francisco.

That night, the Vikings activated rookie defensive end Danielle Hunter, a third-round draft pick. Trattou understood. He’s the fifth defensive end on a team with five defensive ends. Plus, he’s an undrafted five-year veteran with more weeks on NFL practice squads (19) than regular-season games played (17).

Sunday, Hunter and Trattou switched places. Trattou backed up right end Everson Griffen and ended up playing a key part in securing the 26-16 victory.

The Vikings led 23-10 early in the fourth quarter. The Lions had the ball at midfield after a 27-yard pass interference penalty on Xavier Rhodes. Lions quarterback Matthew Stafford dropped back to pass, saw his target and figured he could rifle the ball past the third-string defensive end at close range.

“I was supposed to peel off on the running back, so that’s why I wasn’t coming hard after the quarterback,” Trattou said. “I kind of knew the area he was trying to throw it and just got into his window. I put my arms up and pretty much trapped it into my body because it was thrown so hard.”

It was Trattou’s only snap in pass coverage this season. According to Pro Football Focus, that’s, well, pretty doggone good.

Floyd was a freshman at Florida when he met Trattou. As a youngster from Philadelphia, Floyd was purposely paired with the fellow Tri-State area kid from Maywood, N.J. That’s how Floyd and Trattou became workout buddies and friends.

“We became Gatormates,” Floyd said.

Trattou won two high school state titles at Don Bosco Prep, a private school in Ramsey, N.J., and a national title when he picked Florida over Notre Dame.

When Trattou went undrafted in 2011, 10 teams called to sign him as a free agent. He picked his hometown Giants, a team that was loaded at defensive end.

“When I went to Florida, they had just won the national title,” Trattou said. “I wanted to play with the best. When I had a chance to go to the Giants that year, I went.”

Trattou not only made the team, he played in Week 1. He has a Super Bowl ring from that season, although he was inactive for the upset victory over the unbeaten Patriots.

Trattou spent the entire 2012 season on injured reserve because of injuries to his ankle and heel. But that was the year he thinks he saved his career.

Justin Trattou played Sunday, surprise enough, and soon he had his hands on the ball and QB Matthew Stafford on his ankle.

“I had been 270 pounds and was trying to be a bigger, heavier player,” he said. “But I found out that I’m at my best at 255, which is where I am and where I’ll stay. I’m faster at this weight.”

When the Giants needed running backs in 2013, Trattou was released. The Vikings signed him the next day. He played the season finale that year and spent the first 13 weeks of last season on the practice squad.

“I wanted to play, but not many people can make $100,000 in four months of practicing football,” he said. “So it wasn’t the end of the world. I treated every practice like it was a game. You can ask [left tackle] Matt Kalil. I made his practices harder. And he made me better.

“It’s taken me five years to get to this point. So however many snaps they give me, I’ll take it.”