Can the 49ers restore a defense that not long ago consistently ranked in the top five in the league?

The team has used a first-round pick on that side of the ball in the last four drafts, and 49ers defensive coordinator Jim O'Neil believes the team may have someone special on its hands in 2016 fifth-round pick Ronald Blair.

“I think he’s had a really good training camp. Doesn’t matter what group he plays with. He finds a way to make plays," O'Neil told reporters Thursday in Santa Clara. "He’s very different than anything else we have in that defensive line room.

"He’s a good change-up for us. But, I’ve been very impressed with him.”

Blair is standing out in ways other players aren't, bringing a unique skill set, O'Neil said.

“His ability to get off the ball, slip blocks, use his hands, pass rush. He’s different," the defensive coordinator added. "He’s not that 320-pound man that’s going to knock you back at the line of scrimmage like some of the other guys are built. He’s more of a single-gap penetrator who can make some plays in the backfield. So, he’ll do well for us.”

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A hybrid defender in the front seven checking in at 6-foot-4, 270 pounds, where might Blair ultimately fit?

“We’re playing him everywhere right now. We’re trying to find that out," O'Neil told reporters. "He’s playing some on the edge. He’s playing some inside. He took a couple snaps yesterday at nose.

"But, he can be a problem athletically for guards and centers, just with his skillset. So, that’s something we’re going to work through in the preseason and try to find out where he can best help us along the front.”

Blair over two seasons at Appalachian State racked up 114 total tackles, 32.0 tackles for loss, 12.5 sacks, one forced fumble and one fumble recovery.

He even had one interception he took back for a 30-yard touchdown.

While Blair is a Mountaineers alumni, a smaller school in terms of competition, the scouting department and coaching staff always remained high on his ability.

They weren't at all second guessing what he can do against NFL talent.

“No, because if when you watch the Clemson game from last year, you watch the tape and you love the kid," O'Neil said of a game Blair had eight tackles in, including two sacks of Heisman finalist Deshaun Watson. "I know [general manager] Trent [Baalke] and his staff fell in love with him. They really, really liked him, and he’s a guy that we were going to target in those middle rounds and he was there at the right time and we got him.”

Blair isn't the only player on the roster from Appalachian State. Starting center Daniel Kilgore was similarly a fifth-round pick out of the same university in 2011.

As a rookie, Blair figures to give the 49ers options in the front seven, depending on packages and down-and-distance situations. Working on the edge, he may also chip in while starting outside linebacker Aaron Lynch serves a four-game suspension.