In a few days, we will know whether Jasper Brinkley is really ready to be the man in the middle.

The Vikings have been waiting for this for a long time. They planned for it when they decided to let E.J. Henderson go, enabling Brinkley to ascend to the top of the depth chart at middle linebacker. They hoped for it while Brinkley was out of action for an entire year after a hip injury, subsequent surgery, months of rehab and frustrating offseason setbacks.

They waited for it, as Brinkley used training camp and the first couple of preseason games losing rust and finding a rhythm.

The question is, does he have it?

Like most starters, Brinkley didn't play in the team's preseason finale on Thursday night in Houston. But the team and Brinkley were pleased with what they saw in the third preseason game, when Brinkley finished second on the team with four tackles, had two sacks and three quarterback hits.

"Very important," coach Leslie Frazier said. "Because we were concerned going into the preseason because of his health and what has happened in the past year. So, to see him incrementally get better as time has gone on, and then for him to play as well as he did in the third preseason game, that's encouraging for our entire staff. We feel much better about where he is now than we did prior to that game."

That concern was obvious, when lingering injuries kept Brinkley out of some organized team activities and then the only mandatory minicamp. When Brinkley started out slowly in training camp, that level of concern rose.

Brinkley said he never lost his confidence. But he needed time.

"I had weeks to get ready," he said. "Starting with training camp, up though the preseason. I played decently in the second preseason game.

"In third game, though, I felt I had my legs back under me, my eyes in the right place. It just took time, and it took games. Now I feel I've had enough time and I'm ready to go."

The team has a very specific role for Brinkley, who is a big, physical player. He will play only in the base defense, as a hard-hitting leader against the running game. That means he could play only about half of the defensive snaps. It is not a huge role, but it is an important one.

And Brinkley looked the part against San Diego.

"He played well," defensive coordinator Alan Williams said.

"When he had a chance to make a play, he made it. I told the guys in a meeting that when you have a chance for a layup, don't lay it up. Dunk it with two hands."

Brinkley came free on blitzes twice, one of them called, one of them off his own read. Both resulted in sacks. Williams noted that Brinkley showed good lateral quickness, making plays outside the numbers.

"He had a chance, and he made the best of his opportunities," Williams said.

But is that game a good measuring stick? San Diego sat many starters, so Brinkley and the Vikings defense were going against several second-teamers. That's why there still is some question about the Vikings' defensive strength up the middle, including Brinkley.

That's what makes the opener against Jacksonville so big for him. And why his biggest challenge come Sunday might be containing his emotions. Brinkley hasn't played in a regular-season game since the end of the 2010 season, but he spent countless hours getting ready for his return.

"I'm pretty sure my emotions will be everywhere," he said. "I'm blessed just to have the opportunity to play this game after I was out for a whole year. I know I'll be excited. Heck, I'm excited right now, just because of the simple fact that this injury easily could have been a career-ending injury."