Chemistry is no backroom science project when it comes to the NFL these days. It ranks right up there with post patterns and safety blitzes. It's as important as having a sound game plan or a good draft.
Bottom line is, team chemistry can mean the difference between winning and losing.
The Patriots started the 2001 season with a 1-3 record, yet recovered to win the AFC East and upset the heavily favored St. Louis Rams in the Super Bowl.
"The thing I learned last year," said Patriots safety Lawyer Milloy, "is it's not what you've got on paper, but how you play together."
The Ravens went the entire month of October two years ago without scoring a touchdown. But a change of quarterbacks and the absence of malice sent the Ravens rolling through the playoffs to win the Super Bowl as a wild-card team.
The remarkable part of the Ravens' success wasn't their postseason domination, but the fact that push never came to shove during the touchdown drought in a locker room filled with great expectations and big egos. Peace was achieved largely through the vigilant effort of coach Brian Billick.
"I think Coach Billick did a good job of keeping us grounded," said Ravens tackle Edwin Mulitalo. "I think everyone bonded from that. ... I'm sure [the defense] felt some animosity, but it never leaked out."
Creating good chemistry on a football team is a delicate balance that involves selecting the right players, providing a positive work atmosphere and getting everyone to pull in the same direction.
It may be even more important in today's era of salary caps, free agency and revolving-door rosters. Talent is spread much more equally around the league, and intangibles can make a big difference.
A team that starts the season slowly isn't necessarily buried by that start, either, as the Patriots proved last year. They won their last nine games, including the postseason. The year before, the Ravens were 5-4 after their drought, but ran off 11 straight wins to finish the season.
Success always comes down to execution on the field, but it often starts with camaraderie in the locker room.
"It's real important," Ravens tackle Jonathan Ogden said of the role chemistry plays on a winning team. "If a team doesn't work well together, if things get tough -- and it's going to be tough every Sunday -- you're not going to respond the way you need to if you don't have team chemistry."
The bond of working through problems together is what counts.
"It's like your family to a degree," Billick said. "Nothing says you have to like your brothers and sisters. But they're still family. It doesn't mean you have to love one another, necessarily, but you have to respect one another. You have to deal with one another."
The NFL landscape is littered with examples of personal conflicts. Sometimes those conflicts grow into something bigger and divide a team.
A year ago, wide receiver Terrell Owens and coach Steve Mariucci of the San Francisco 49ers had a public falling out. It took Mariucci's visiting privately with Owens in the off-season to patch up the rift.
When the Tampa Bay Buccaneers lost in the first round of the playoffs for the second straight year, wide receiver Keyshawn Johnson criticized defensive tackle Warren Sapp, and the two have been less than cordial since.
This summer, the Miami Dolphins cut defensive tackle Daryl Gardener in the name of team chemistry after he failed to respond to any of coach Dave Wannstedt's inquires about his absence from the team's off-season conditioning program.
Billick says football is the ultimate team sport because of the numbers involved.
"In order to be champion, all 53 guys at some point are going to play a factor in your season," he said. "Just by those sheer numbers -- 53 guys -- that's a lot of people to orchestrate. That's a lot of personalities."
Billick was at his orchestrating best two years ago when the Ravens were locked out of the end zone. They went into October with a 3-1 record and won the first two games of the drought to go 5-1. But as the streak deepened and three losses followed, Billick took measures to preclude an incident that might disrupt locker room harmony and worsen the situation.
He talked endlessly about the importance of staying together. He peppered the team almost daily with examples of league-wide dissension, punctuating his lecture with the question, "Is this what you want to be?"
Billick also reinforced team leadership. A triumvirate of Ray Lewis and Rod Woodson, two defensive stars, and tight end Shannon Sharpe, a leader on offense, served to quell any potential problems.
Billick provided a commanding presence, but it would be up to the players in the end.
"Certainly as a leader, you need to be out there leading at times," he said. "But more often than not, it's kind of, 'Get behind the players and push them in the right direction.' That's a better way to lead, because they're ultimately going to be the ones on the field."
Likewise, the Patriots followed the lead of coach Bill Belichick through a tumultuous and tragic training camp a year ago. Joe Panos, a starting guard, retired the first day of camp. Andy Katzenmoyer, a starting linebacker, walked out with an injury that effectively ended his career.
In August, quarterbacks coach Dick Rehbein died suddenly of heart failure. In the regular season, the Patriots lost franchise quarterback Drew Bledsoe to injury and malcontent wide receiver Terry Glenn to suspension.
They overcame all those distractions in part because Belichick maintained a resolute presence at the helm.
"It was the leadership from the head coach, the fact the players believed in the head coach and believed in themselves," said Scott Pioli, the Patriots' vice president of player personnel. "And at every turn at different points in time, there were players who stepped up and helped us through adversity."
Pioli said the concept of chemistry is part of the Patriots' player evaluation equation.
"I think we're definitely looking for players with a certain type makeup and character traits," he said. "I think what's important for us is that we have an understanding of what type of player is going to be successful in our program. One of the first components in getting a player to be successful is getting a player in here who can follow the leadership of the leader."
That means buying into the coach's system.
"Believing in the coach's system, believing in the guy next to you and believing it's going to work is huge," Ogden said. "Brian's first year we were 8-8, but ... during the course of the season, we started to buy into what he was selling, and the next year we come out and get it done."
Creating that positive atmosphere was something Billick learned as an assistant under Dennis Green with the Minnesota Vikings.
"I learned from someone I think is one of the best," he said. "When I got this job, it became readily apparent to me how important that was. This concept that people put out there, that somehow to validate myself as a head coach I have to win at some point with offensive brilliance, is almost comical to me.
"I'm a true believer that a head coach, whatever his strengths are, he has a primary job. His primary job has to be to create the best working environment he can for his coaches and players and indeed the whole organization."
Creating that environment out of a hazardous situation proved to be a common denominator the past two years.
"As I've said many times, I don't believe we'd have won the Super Bowl if we hadn't had to fight our way out of that difficulty," Billick said. "Much like, I'm sure, New England, dealing with that initial 1-3 start. You're either going to go one way or the other."
In the case of the Ravens and Patriots, two teams that weren't necessarily the most talented across the board, they went right to the top.
"No matter how much talent you have, if you have the right group of guys and the right attitude with the guys you have on the team, you can overcome anything," said Patriots guard Damien Woody. "And that's pretty much what we did last year. We're trying to build off that success this year."