It’s been a long time since Esera Tuaolo walked into Lambeau Field. He was a closeted player in the NFL the last time he visited the hallowed grounds; This Sunday he will enter as an openly gay man and a groundbreaking figure in the sport’s history. As part of the Green Bay Packers alumni weekend, Tuaolo has been recruited to sing the national anthem before the Pack’s game against the New York Jets.

He sang the anthem before a game once before at Lambeau Field. It was Oct. 17, 1991, a Thursday night game against the Chicago Bears, and he was a rookie defensive end for the Packers. It was hard enough that he was in the middle of a season in which he became the first rookie to start all 16 games for the Packers and he had to play moments after singing (that had never been done before in the NFL). But the worst part of the evening was when he got home after the game.

"When i got home I had tons of messages from people saying that they saw me sing," Tuaolo told Outsports. "I didn't know they were going to broadcast it. I thought it was just for the people at the game. And that freaked me out becuase everyone around the coutnry saw it. I had a panic attack because I was worried that someone I had been with before saw me sing and they would say something."

No one said anything, and Tuaolo continued his NFL career deep in the closet.

Now, a dozen years after coming out publicly, Tuaolo is looking forward to returning to Lambeau Field as an openly gay man for the very first time.

"Its an honor to sing the national anthem for the team that gave me my chance," Tuaolo said. The Packers drafted him in the second round of the 1991 NFL Draft.

"But this time I get to walk into that stadium as an openly gay man. When I did it before I was a closeted gay man. This time everyone will be cheering for me for who I really am. It will be emotional. I've entered into that stadium fighting depression and fighting everything that comes with being in the closet. Sunday will be emotional."

Tuaolo has been watching Michael Sam's journey with great interest. Unlike Tuaolo, Sam is openly gay in the NFL. But just like Sam, he was a pass-rushing defensive end. Tuaolo was the last person to record a sack against John Elway.

"I know what he's going through. I can compare myself to him or anyone who's played int he NFL. Getting released is tough. But the amazing thing about it is that the kid can flat-out play. He's a great ahtlete and he's only going to get better. And the great thing about it is he's going to be able to be himself, something that I was never able to do in the NFL, being able to have your partner in the wives' section, those small little things that my straight friends took for granted."

Now Tuaolo is mounting a campaign to sing the national anthem at the Super Bowl. You can check out his "audition" below – or before the Jets-Packers game this Sunday.

Tuaolo sang the national anthem at LGBT Night with the Los Angeles Clippers in 2011: