The voice on the other end of the line produced a knowing laugh, one confident in the knowledge gleaned from 15 years in NFL locker rooms. In Matt Birk's estimation, the players' sanctuary is the last place to expect problems for Missouri defensive end Michael Sam, whose historic announcement Sunday makes it likely he will be the first openly gay man to play in the NFL.

"I would put it like this," Birk said. "Over the years I can think of 10, maybe 12 guys that I played with that I know are gay. Everyone on the team knew they were gay, and they knew that everyone knew they were gay. They didn't take that step of going public, but it never was an issue in my experiences.

"I get why this is an issue, especially when you look at the bullying story with [Miami Dolphins offensive linemen] Jonathan Martin and Richie Incognito. I get why people would be concerned. But I think we really underestimate football players sometimes."

Fourteen-year NFL veteran Matt Birk said he played with gay teammates whose sexuality was no secret in the locker room and that it was never an issue. Ron Chenoy/USA TODAY Sports

NFL locker rooms are home to 1,952 players between active rosters and practice squads during the season. As in life, their personal viewpoints run the gamut. Some are passionate about social issues, others clueless. I sought out Birk's thoughts because I believe he occupies the nuanced position of the silent majority: Those who have personal beliefs but understand their limited relevance within the team concept.

Birk, as you might recall, publicly supported an amendment to the Minnesota constitution in 2012 that would have formally banned gay marriage. At the time, he was completing his fourth and final season as the Baltimore Ravens' center after 11 years with the Minnesota Vikings. Birk immediately faced the assumption that he was homophobic as well, but he has used that intersection as a platform to point out the distinction between political beliefs and interaction among NFL players.

"There is a difference between trying to talk about what marriage is and what my feelings are toward individuals," he said. "There are actually many people that are close to me that are gay. ... But in the end, the issue is someone's sexuality: Does it really ever come into play at work? I don't think so.

"I know there are stereotypes about football players and what the locker room is like and all that. Some of those stereotypes, sometimes we're our own worst enemies. We take advantage of all the perks of the locker room. Sometimes that means you act like a teenager. But when push comes to shove, when you're talking about something like this, this serious issue and monumental of an issue, I really think football players will answer the bell."

Of course, the difference between the NFL and other working environments is the locker room itself. So as long as Birk brought up the issue of stereotypes, I figured I would ask the "shower question." Once again, Birk laughed.

"That's the biggest stereotype there is," Birk said. "Like I said, if you play in the league for any amount of time, you play with gay teammates. And you've showered with them, and you probably knew it, too. That's going to be an issue the media focuses on much more than players."

Birk suggested, and I agree, that Sam's biggest impact on the locker room will occur the first few intense days he is there. Teammates, coaches and front office members will face questions from reporters that veer far from their area of expertise.

"But that should be it," Birk said. "After one or two days, it's back to football. That's why everyone is there -- for football."

"This is more of a general statement, but most people don't care about anything nearly as much as they care about themselves," Birk added. "We're pretty selfish as human beings. At the end of the day, I really think most guys are going to be concerned about going to work, doing their jobs and keeping their jobs."

And that's the key, isn't it? Most guys. Michael Sam will play alongside at least some players who would prefer he kept his orientation to himself. Others will defend and support him passionately. The rest? Most guys, I think, will move past the initial attention and, whatever their personal beliefs are, do their jobs.