PHILADELPHIA — Fresh off a Super Bowl appearance with San Francisco, Eagles defensive tackle Isaac Sopoaga is expecting big things from his new team in the 2013 season.

“We are here to hunt. We are here to win,” Sopoaga said during his introductory news conference at the NovaCare Complex. “I promise you that we are going to shock the world.”

Sopoaga wasn’t predicting the Eagles’ first trip to the Super Bowl since the 2004 season, but he believes that new Eagles coach Chip Kelly’s innovative offense and an aggressive defense will take the NFL by surprise.

Kelly, who was hired on Jan. 16 to replace Andy Reid, is regarded as an offensive guru who lit up scoreboards with a read-option attack at the University of Oregon.

“ I think it’s evident when you watch Isaac play on tape the passion that he has for this game, and that’s why we want him to be part of our organization,” Kelly said Wednesday while introducing Sopoaga and tight end/fullback James Casey. “And if you don’t plan on coming in here and winning then we’re not going to talk to you. So the statements that he makes is exactly how everybody in this football program feels and what it’s all about.

“But we also know that it’s not about talk because what you say in March and what you say in April doesn’t really have anything to do with what you do on Sundays.”

Sopoaga and Casey are expected to play big roles on the defense and offense, respectively, but they also were signed to provide some much-needed leadership.

That quality was lacking in the Eagles’ locker room the last two years, which partly explains their 12-20 record in that span. Middle linebacker DeMeco Ryans, defensive tackle Cullen Jenkins and quarterback Michael Vick tried to fill the void but are more prone to lead by example.

When Kelly and general manager Howie Roseman began preparing for the free-agency signing period, they focused on players who could help both on and off the field.

They are counting on Sopoaga, Casey and other newcomers such as safety Patrick Chung to not only upgrade the team on the field but also change the culture. It was not a coincidence that three of the five players they signed on Tuesday — Casey (Houston), Chung (New England), Sopoaga (San Francisco) — played for teams that reached the playoffs last season. They also signed cornerback Bradley Fletcher, who played for St. Louis last season, and Carolina linebacker Jason Phillips.

“It was important for us to get the right people for our team not only schematically, but also culturally,” Roseman said Wednesday while introducing Casey and Sopoaga to the media. “We went after guys who would be the right fit for us. The character, durability and level of play all factor into going after a player.”

Casey is expected to have a huge impact on the offense as a hybrid player who can line up at tight end, fullback and maybe even wide receiver.

And if the Eagles ever need an emergency quarterback, he could be a candidate. Actually, both Casey and Sopoaga claim to be able to throw a football 75 yards.

“Houston wanted me back, but I thought this was a great fit for me,” said Casey, who also played professional baseball for three years before turning to football. “It was a pretty easy decision for me to sign with the Eagles. Every player wants the opportunity to fulfill his potential and hopefully I’ll get the chance to showcase what I can do and help this team win.

“I’m excited to be here, excited to get to know the city of Philadelphia and get to work, getting to meet my teammates and doing everything I possibly can to help the Eagles win. Coming to a great city was part of it. I know the Eagles have a huge fan base and they’re really die-hard fans and that’s going to be fun to play for fans like that.”

Kelly envisions using Casey and Eagles veteran tight end Brent Celek in a variety of roles similar to the way New England uses Rob Gronkowski and Aaron Hernandez.

Wide receivers DeSean Jackson and Jeremy Maclin will have their plays, but Kelly favors bigger, more physical guys who can both stretch the field and punish defenders.

“The NFL is a big-man’s game and we want big, athletic guys who can run,” Kelly said Wednesday. “You watch the Patriots and you can see how they can make things very difficult for defenses. We want to be able to keep defenses on their toes.”

The Eagles still have more work to do in the offseason.

Defensive lineman Ricky Jean-Francois, Sopoaga’s 49ers teammate, visited the Eagles on Wednesday, but no deal was reached. They also need to upgrade several other positions — offensive line, secondary — either via free agency or through the draft.

Both Kelly and Roseman stressed the desire to add players who not only have talent but also a strong work ethic.

“That’s the key for us,” Kelly said. “We need to get a bunch of guys that aren’t afraid to get down and dirty and go to work. We’re in a blue collar town, we’ve got a bunch of blue collar guys that are going to go to work every single day, and we’ll pick our heads up sometime next January and figure out if it was good enough.”

Extra points: Roseman and Kelly refused to tip their hands regarding the Eagles plans for next month’s draft. ... The Eagles have the fourth overall pick. ... Roseman, Kelly and even owner Jeffrey Lurie traveled to Morgantown, W.Va., last week to work out and talk to West Virginia quarterback Geno Smith.

“I don’t know (if the Eagles are going to draft a quarterback),” Kelly said. “Just because it’s quarterbacks, I think people get enamored with that. Our job is to win on Sundays and we’re going to look at anybody and everybody to see if we can win games.”

Contact David Weinberg:

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