Trent Baalke: Arik Armstead a rare player

SANTA CLARA, Calif. -- San Francisco 49ers general manager Trent Baalke gave an added insight Tuesday night into why he selected defensive lineman Arik Armstead with the No. 17 overall pick in last spring’s draft.

It was a fit neither he nor rookie coach Jim Tomsula, the team’s defensive line coach since 2007, could pass on.

“What Arik Armstead can do, physically, and the technique he can play, in any given draft, there’s only five, six guys that we have on our board that can play a 4-technique in the NFL, a true 4-technique -- two-gap, leverage, clip, all that stuff at the line of scrimmage -- and for us to play the type of defense we’ve played for the last six years with Jimmy T, we’ve got to have that ability. We’ve got to have those guys.

“Justin [Smith] was obviously excellent at it, and Ray [McDonald] was excellent at it and we’ve always had competent noseguards.”

In Armstead, who missed most of the offseason training program due to school still being in session, the Niners selected a player out of Oregon who only had four career sacks in 39 games.

“I had to catch up the best I could by working out on my own, trying to get in the best shape I could and I had my iPad and chalk study as much as I can,” Armstead said. “I was a little bit behind not being able to do OTAs, but I’m excited to make those [exhibition] games and training camp.”

And with Smith retired and McDonald cut last December in the wake of numerous brushes with the law, the likes of Armstead, Quinton Dial and Tank Carradine will have to join with Darnell Dockett and Glenn Dorsey to pick up the slack.

“Now we’ve got a group of guys that are younger, a little less proven, but they’ve all also proven they can do it,” Baalke said. “Now they’re going to get a chance to get more reps and with more reps they get better. They improve.”