Waters signed with the Patriots before the season after toiling 11 years in Kansas City without winning a playoff game. He now has a chance to be part of a Super Bowl champion if New England can beat the New York Giants on Sunday.
"You just only get so many opportunities at it," said Waters, a six-time Pro Bowl player for the Chiefs. "I knew that as I got older, that the chances were getting slimmer and slimmer."
It's been quite a climb for the soon to be 35-year-old Waters.
"I'm happy for Brian," said backup lineman Nick McDonald. "Twelve years and he wins his first playoff game this year."
McDonald is at the opposite extreme, a seldom-used player with a shot at his second Super Bowl ring in his two seasons. He made the Packers as a free agent out of Grand Valley State in 2010, but was a healthy scratch in all 16 games and four postseason games. He played in six games with the Patriots this season, including two in the playoffs.
"The good luck charm," Waters called him.
Waters was 0-3 in the playoffs with the Chiefs, but he's 2-0 with the Patriots and surrounded by plenty of talent on the offensive line, with veterans Matt Light and Logan Mankins protecting Tom Brady's left side. Waters keeps defenders from coming up the middle at the star quarterback.
"We know that is a key part of being successful as a football team," Waters said, "to make sure that Brady stays clean and gets an opportunity to get the ball out to those special players that we have out there in the skilled positions."
The line has done a good job of that, limiting opponents to 32 sacks in the regular season and one in two playoff games.
New York's defensive linemen are healthier now and "are doing a lot more things as far as how they are scheming up and moving people around," Waters said.
But he's a knowledgeable veteran who studies the individual strengths and weaknesses of opponents. And he's a powerful blocker.
"One of the things that stands out is he's a really strong guy," Giants defensive tackle Chris Canty said. "He gets those hands on you and you're not really going anywhere."
Especially if he gets too tight a grip and the officials don't call a holding penalty.
The main thing to worry about when trying to beat his block?
"Him grabbing," said Linval Joseph, the Giants' other starting tackle. "I just have to try to stay out of his zone because he's really good at holding you down. He has really strong hands. He has a lot of experience, so he's very good at what he does. You try to keep his hands off you."
The Patriots went into training camp with an opening at right guard caused by the retirement of Stephen Neal. Dan Connolly was a candidate to start at that spot, but his chances dimmed when Waters arrived.
Still, Connolly embraced the Patriots' way of team first.
"One of the first guys that greeted me through the door was Dan Connolly," Waters said, "but he was one of the guys that I was going to be competing with for the job. That just showed that this team is all about team. It's not about individual stuff."
Connolly lost out on the spot at guard, but became the starting center when Dan Koppen suffered a season-ending knee injury in the opener.
"I have a great respect for Brian and when he came in I didn't see it as threatening at all," Connolly said. "The way it worked out I still got to play and he got to play, so everything worked out in the end."
On Sunday, they'll line up side by side, working hard to protect Brady and win a Super Bowl, a missing piece from Waters' exceptional career.
"Talking to other players who never got the opportunity to experience this, it's definitely something where a lot of guys feel a void, but you also have to take solace in that fact that not too many people get to play this game," Waters said.
Finally, he has his chance.