"There’s not much he can’t do," Mangini said. "You appreciate just the volume of moves that he has. How easily he does things that it takes a long time for other guys to learn to to do what’s natural for him, instinctual."
But what Smith hasn’t done the last two years is stay on the field enough to contribute in the same capacity he did during his first two seasons in the league.
Over the last two seasons, the former seventh-overall pick missed a combined 14 games. He left the team and missed five weeks to attend an in-patient treatment facility in 2013 following a September DUI arrest, and then received a nine-game suspension last year for violating the league’s substance abuse and personal conduct policies, stemming from the DUI and weapons charges from a party during the summer of 2012.
For now, the upcoming season is a clean slate for Smith, who has a chance to play a full 16-game schedule for the first time since 2012, when he notched 19.5 sacks and was named a first-team All-Pro.
It’s no coincidence the 49ers reached the Super Bowl that season and had the league’s third-ranked scoring defense. Smith’s 33.5 sacks in his first two seasons were the most over a two-year span in league history.
And with San Francisco losing two starting corners, along with inside linebackers Patrick Willis and Chris Borland this offseason, Smith returning to that form could go a long way toward masking the transition period his team is going through on that side of the ball.
"When I look around the locker room, I see a lot of new faces. That’s all," Smith said. "If anybody underestimates us, that’s their problem. We’re confident in ourselves that we’ll be where we need to be when the season starts."
Like last season, before his nine-game suspension was announced, Smith has looked dominant on the practice field in the early going of training camp. He says he’s in the best shape of his life, and has kept his name out of the police blotter, allowing him to play football worry free.
To new head coach Jim Tomsula, who worked closely with Smith when he coached the defensive line during Smith’s first four seasons, Smith’s reinvigoration hasn’t gone unnoticed.
"I’m really happy for, and excited for Aldon. I respect what Aldon’s doing. And I respect the road he’s on," Tomsula said.
"Life throws some things at you, man. Sometimes you cause it, sometimes you don’t. Things happen. To me, the answer’s always in you. The answer’s not if it’s going to happen, or what’s going to happen, the answer is always in how you handle it and where you go from there. Own it, fix it, let’s go. The work, obviously the shape he’s in, the conditioning he’s doing, I am really excited for Aldon."
In Saturday’s first practice of training camp, Smith beat his blocker and got to the quarterback during full-team drills, but was unable to make the hit as he would in a game. Instead, he ran past the Colin Kaepernick, and tilted his head toward the sky in frustration. He wanted to make the hit, perhaps because those instances came less frequently last season than what he was used to.
After returning from his nine-game suspension, Smith notched just two sacks in seven games, averaging less than a sack per game for the first time in his career.
But if he’s going to become the player he was in 2012 this season, he’s going to have to do it with a new running mate to his left. No longer will he be running pass-rushing games with Justin Smith, who also retired this offseason. Instead, Smith will be working alongside the likes of Glenn Dorsey, Quinton Dial, Tank Carradine and Darnell Dockett.
"Anybody that’s filling Justin’s spot, we’re going to have to create chemistry with,” Aldon Smith said. “That’s the guy who’s been beside me since I’ve been here. People learn fast, we got a good coaching staff and a good group of guys who make everything easy so it will work out."
Despite his off-the-field history and pending suspension, the 49ers last May picked up Smith's "fifth-year option," which guaranteed his $9.754 million salary in 2015 for injury. But this offseason, the team restructured the deal with Smith before his money became fully guaranteed.
The restructure converted the guaranteed money into monthly roster bonuses, allowing the 49ers to cut bait should Smith run into off-the-field issues for a third-straight season, according to reports from CSN Bay Area and the NFL Network.
The deal was also a good-faith effort by Smith, who gave the 49ers insurance for backing him throughout his string of transgressions. A good year for Smith, both on and off the field, could lead to a new extension with San Francisco before he hits free agency in the spring.