FLOWERY BRANCH — Mike Smith says he doesn't want his Falcons defense to be predictable or easily labeled.

Second-round draft pick Ra'Shede Hageman is a very big reason Atlanta may no longer be easily cast as a 4-3 defense.

Hageman (6-6, 318) played nose tackle at Minnesota and was drafted as a defensive end. That's a strong signal there will be an increased emphasis on a 3-4 scheme. Players who look like offensive tackles don't often play defensive end in four-man fronts.

Following Friday's first session of the three-day rookie minicamp, Hageman gave an even stronger signal of the changes planned in Atlanta when he discussed the adjustments he must make in the NFL.

"In college I played a 4-3 but now we play a 3-4," Hageman said.

Oh.

Smith hasn't gone that far in revealing his plans. He only says he expects the Falcons' defense to be multiple.

"We don't want to be pigeon-holed as 'this defense' or 'that defense,'" Smith said. "I think when you really study how people play defense, and how we play defense, you don't know what we are, and that's the key."

Whatever the scheme, the Falcons need to improve a pass rush that produced only 32 sacks in 2013, tied for the league's third-fewest.

Defensive end Osi Umenyiora, who led the team with 7 1/2 sacks, will return. Defensive tackles Corey Peters, Jonathan Babineaux and Peria Jerry, who combined for 12 1/2 sacks, re-signed as free agents.

The Falcons added defensive end Tyson Jackson and defensive tackle Paul Soliai in free agency.

Hageman impressed Smith and his assistants, including defensive line coach Bryan Cox, as the Atlanta staff coached in the Senior Bowl.

"Just the way they coached me down at the Senior Bowl, there was great chemistry with the coaches," Hageman said.

"I didn't know what team was going to draft me but I'm glad the Falcons did to kind of put me in a situation to take advantage of my potential."

The Senior Bowl assignment was a first for Smith. The Falcons finished 4-12 in 2013 following winning records in Smith's first five seasons.

Smith said having the full week with such draft prospects as Hageman at the Senior Bowl was an unexpected bonus.

"Absolutely, it wasn't on my bucket list as one of the things I wanted to do as a coach, but once we had the opportunity to do it, we embraced it as an organization and I think it was very beneficial," Smith said. "I talked to a lot of guys that had done it before and that was one of the points they made to say 'Hey when you get ready to prepare for the draft, you will have a leg up on everybody else' and I felt like we did."

Hageman had 10 sacks in his career and 24 tackles for losses. He also blocked two kicks.

"Ra'Shede is a big man, knocks a lot of balls down, pushes the pocket, he shows athleticism to make people miss," Smith said. "It is important to have push. I say it all the time, sometime sack numbers are overrated. It is about making the quarterback uncomfortable."

Friday's drills were conducted at a walk-through pace with no pads. Hageman had chances to line up against Atlanta's first-round pick, offensive tackle Jake Matthews of Texas A&M.

"Just the fact that you're going to go against him one-on-one every day is going to make you better and make him better," Hageman said. "It's a great situation."

Some of the matchups may not have been as non-contact as planned.

"Coach had to tell us it was a walk-through," Matthews said. "Guys were going full-speed and we're busting lips and hitting guys and busted my nose up. We were getting after it. That's the big thing that I take away from this, that these guys love to work and I'm glad to be a part of the group."

NOTES: The Falcons had 53 rookies for the opening day of the camp: nine draft picks, 20 players who signed as college free agents and 24 invited as tryout players. ... Matthews is wearing No. 70. Hageman is No. 77. Running back Devonta Freeman, a fourth-round pick from Florida State, is No. 33 — Michael Turner's old number.