ALLEN PARK, Mich. -- Detroit Lions defensive coordinator Gunther Cunningham saw the jaw-dropping collision and immediately knew one thing: Outside linebacker Ernie Sims was in trouble. Sure enough, within seconds of cracking an unsuspecting running back during a training camp noncontact drill, Sims faced a steady stream of verbal abuse from new Lions head coach Jim Schwartz.
But what Schwartz couldn't see was the grin forming on Cunningham's face at the time.
"I had to support Jim because you don't want players getting hurt in practice," Cunningham said. "But I also gave Ernie a little thumbs-up after Jim was done with him. I like seeing that aggressiveness in him."
What the Lions also need to see this season is more of the old Ernie Sims. The fourth-year veteran was once hailed as the second coming of former Tampa Bay Buccaneers star linebacker Derrick Brooks and he even had many people wondering why he was snubbed from the Pro Bowl in 2007. Last year was a different story. Just as the Lions produced a dismal 0-16 record and fielded the NFL's worst defense, Sims stopped reminding people of why his star shone so bright in the first place.
So after seeing his production decline in 2008 -- he had a career-low 113 tackles -- Sims is out to show everybody how quickly things can change.
"Last year was tough as hell," Sims said. "I've never been through anything like that because I've always been a winner. But dealing with that season definitely made me a better player. I realized that if I can get through something like that, then I can pretty much get through anything."
The reason Sims has to be more optimistic about this coming season is the Lions' new defense. After spending the past three years playing in the Cover 2 scheme preferred by former head coach Rod Marinelli, Sims is stepping into a more aggressive system that allows linebackers to force the action. Gone are the days when he had to fill his gap while his teammates filled theirs. Now Sims can play with the same instinctive relentlessness that always has come naturally.
What I said to Ernie early on is that this scheme is based on a see-ball, get-ball attitude. Just saying that to Ernie put a smile on his face and brought him out of his shell.
”-- Lions defensive coordinator Gunther Cunningham on the team's new scheme and LB Ernie Sims' reaction
He couldn't do that last season, when he too often put himself out of position while trying to make plays. Now he's back in a role that is very similar to what he did during his standout career at Florida State.
"The reason I like this defense is that I get to play downhill again," Sims said. "That's how I've always liked to play -- fast and explosive. Last year I had to run backwards a lot. Now I get to play with more freedom."
"This defense benefits a guy like Ernie because it lets the linebackers play with their eyes," Cunningham said. "What I said to Ernie early on is that this scheme is based on a see-ball, get-ball attitude. Just saying that to Ernie put a smile on his face and brought him out of his shell."
Sims also should be thrilled by two of the smartest offseason moves the Lions made this spring: the trade that brought former Seattle Seahawks linebacker Julian Peterson to Detroit and the free-agent signing of former Pittsburgh Steelers linebacker Larry Foote. Peterson is a five-time Pro Bowler who can help the Lions in blitz situations. Foote has two Super Bowl rings from his seven seasons in Pittsburgh. Just being in the same meeting room as those players will help Sims grow as a player.
As Peterson told Sims shortly after joining the team, there's no reason for Sims to feel like he has to do everything by himself anymore.
"We always talk about football and techniques but one the best things J.P. [Peterson] told me was that I have some players to help me now," Sims said.
"That was important for me to hear because I've always had dogs around me since I came here. It's good to know I have that kind of support."
Like many young, talented players mired on losing teams, Sims will be aided by how much he trusts the new regime in Detroit. He believed in what Marinelli was doing but that dedication ended with Sims' playing on the first winless team in the era of the 16-game schedule.
Now he has to place his faith another set of coaches preaching about big ideas and a new day in Motown. So far, Sims has given Schwartz and Cunningham plenty of evidence that he's buying into what they're selling.
Cunningham likes the way Sims routinely seeks him out in his office to talk about the defense. Sims also surprised his coordinator earlier this offseason by inviting Cunningham to his wedding. The Lions coaches certainly hadn't been around long enough to make that kind of impression on any player.
But that also says something about how willing Sims is to give this new group a chance at turning around the Lions.
What Sims understands is that the Lions can only improve if they all commit to raising their game.
"One blessing of life is that you always have a chance to prove yourself," Sims said.
"And that's what I'm planning on doing this season."
Judging from the conviction in his words and the defensive changes in Detroit, Sims soon will be giving his coaches another reason to smile about his play.
Senior writer Jeffri Chadiha covers the NFL for ESPN.com.