''Those two guys we're counting on,'' Smith said Sunday night. ''They've got to continue to grow from where they were last year.''
Coming off a 4-12 season that ended with their defense ranked last in third-down efficiency, second-worst against the run and third-fewest in sacks, the Falcons still have unfulfilled leadership roles at several positions.
But that's not the case at cornerback.
Trufant and Alford are showing a healthy dose of swagger in training camp, particularly after meeting expectations as first- and second-round draft picks in 2013.
Trufant started all 16 games, played the second-most number of snaps on defense and ranked second among NFL rookies with 17 passes defended.
One of his biggest games was a 27-26 home victory over Washington in Week 15 when his fourth-quarter interception helped set up Matt Bryant's field goal and he batted down a two-point pass conversion attempt in the closing seconds.
''We were always confident, but I think we're just really getting comfortable now,'' Trufant said. ''We've got some new people and we've got some people returning, too, so we're still growing together, but we're flying around out there. We're making plays and we've just got to keep grinding.''
The Falcons' defense struggled last year as injuries affected linebacker Sean Weatherspoon and linemen Kroy Biermann and Corey Peters and cornerback Asante Samuel and safety Thomas DeCoud fell out of favor with coaches.
For Alford, who intercepted Saints quarterback Drew Brees in the season-opening loss at New Orleans, Samuel's demise meant added responsibility, but he says he will always consider his former teammate to be a mentor.
''I started all four years in college, but moving up to the NFL was completely different,'' Alford said. ''Just coming in and being behind Asante, was just a learning experience for me. Even though I got in and played in some games, watching him and seeing how he prepares - that really helped me a lot.''
The remaking of the secondary, and the rest of the defense, began with Samuel and DeCoud getting released last winter.
Veteran linemen Tyson Jackson and Paul Soliai and safety Dwight Lowery were signed in free agency.
Minnesota end Ra'Shede Hageman was drafted in the second round, safety Dezmen Southward in the third round and linebackers Prince Shembo of Notre Dame and Marquis Spruill of Syracuse in the fifth.
Connecticut linebacker Yawin Smallwood and South Dakota linebacker Tyler Starr were drafted in the seventh.
In their third season under defensive coordinator Mike Nolan, the Falcons will mix 3-4 and their traditional 4-3 alignments in hopes of keeping opponents guessing.
One 3-4 alignment has Jackson, Soliai and Jonathan Babineaux as the down linemen, with Biermann and Jonathan Massaquoi as hybrid outside linebackers-ends.
One 4-3 alignment for passing situations uses traditional ends Biermann, Mallicah Goodman and Osi Umenyiora as down linemen alongside Babineaux, who's played most of his career at tackle.
With all the changes up front, Trufant and Alford are trying to keep everything steady in the secondary.
William Moore returns for his fifth season as the starting strong safety. Southward is pushing Lowery to start at free safety.
Alford is encouraging Southward and Lowery, saying regardless of who wins the job, the Falcons will be in good shape.
''You've got to learn your plays and learn where your help is,'' Alford said. ''If you don't have help, you have to learn how you need to play the receiver. It's studying the guys you're going against and putting it together on the field.''
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