FLOWERY BRANCH, Ga. (AP) -- The Atlanta Falcons always talk about having a ''next man up'' mentality.
This time, the next four men are up.
Dealing with the most serious rash of injuries that coach Mike Smith has ever encountered, the Falcons returned to practice Wednesday looking to fill some major holes heading into a game at Miami against the unbeaten Dolphins.
Smith greeted the media cheerily and insisted that nothing has changed for Atlanta (1-1), which came up just short of the Super Bowl last season and wants to go even farther.
His players are certainly on board with that mindset.
''You never like to see guys go down,'' quarterback Matt Ryan said. ''But that's part of the deal, part of the nature of the NFL. Guys are going to get nicked up. Other guys have to step up.''
The Falcons were more than nicked up in last Sunday's victory over the St. Louis Rams.
Two starters - defensive end Kroy Biermann and fullback Bradie Ewing - went down with season-ending injuries. Linebacker Sean Weatherspoon, the emotional leader of the defense, sustained a foot injury that will keep on the sideline for at least two months. Running back Stephen Jackson hobbled off with a hamstring problem and already has been ruled out of the Dolphins game, though the Falcons insist his injury isn't nearly as serious as the others.
Three other key players - receiver Roddy White, cornerback Asante Samuel and offensive tackle Sam Baker - didn't practice Wednesday.
''I don't think there's any shock factor,'' Smith said. ''In the NFL, guys are going to get injured.''
Weatherspoon's spot is the biggest to fill.
A first-round pick in 2010, he had grown into the unquestioned leader of the defense - calling signals, flying around the field, inspiring teammates with his fiery style. Akeem Dent will take on many of Weatherspoon's responsibilities, and former starter Stephen Nicholas will be back on the first team in certain alignments.
None of them measures up to Weatherspoon.
''Sean was a huge emotional leader,'' safety Thomas DeCoud said. ''He was a playmaker for our team.''
Second-year end Jonathan Massaquoi will also be under the gun to replace Biermann, an undersized player who didn't have a lot of sacks but was highly valued on the defense for his versatility. He could play as a down lineman, or morph into an outside linebacker when the Falcons went with a 3-4 - the preferred scheme of coordinator Mike Nolan. There were even times when Biermann dropped deep into coverage, serving as an extra safety.
Massaquoi is not that adaptable, which means the Falcons are likely to return to the 4-3 as their base defense.
''My skill set is different than Kroy's,'' he said. ''The coaches know that. I'm pretty sure they will put me in the right situations to execute my skill set."
The Falcons also signed a couple of veterans, Jamar Chaney and Omar Gaither, to bolster their depth at linebacker. They're getting a crash course in their new team's terminology, but Gaither said it shouldn't take too long to get up to speed.
''They may call the Cover 2 something else, but it's still a Cover 2 at the end of the day,'' he said. ''The most important thing now is learning the communication.''
On the offensive side, Snelling is expected to line up at fullback when the Falcons go with a two-back alignment, as well as sharing time at halfback with Jacquizz Rodgers.
Atlanta should be fine as long as those two guys are on the field. Rodgers was a pseudo-starter last season as Michael Turner's role diminished, while Snelling is a long-time backup who has always stepped up when needed. In the victory over the Rams, Snelling scored on an 11-yard run - the Falcons' longest play of the day on the ground - and he caught a 22-yard pass that sealed the victory.
Things may get a bit trickier if the Falcons have to go deeper on the depth chart. Antone Smith is known more his special-team abilities. Josh Vaughan was undrafted out of college and has rushed for just 31 yards in his career. Patrick DiMarco, the only true fullback on the roster, was waived in the last round of cuts and spent the first two weeks on Atlanta's practice squad.
''These other teams we're playing, they don't care about any of that,'' Snelling said. ''It's a next man up mentality that we have. We're serious about it.''
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