Ross took Seau into his office after practice and showed him film of the play.
"He turned to me and said, 'That will never happen again.' It never did."
Seau committed suicide Wednesday at age 43, stunning the city of San Diego and the football world.
In the following days, Ross and others fondly remembered their favorite moments with the star linebacker, a homegrown superstar who played 13 of his 20 NFL seasons with the Chargers.
In 2002, Marty Schottenheimer was finally on Seau's side, coaching the linebacker in his final season in San Diego.
"Of all the players I've coached, he had the most natural, innate instinct about how to play the game," said Schottenheimer, who had been coach of the division rival Kansas City Chiefs from 1989 to 1998. "And I remember watching him and thinking, 'Where in the heck is he going?' And all of a sudden he made the play and I thought, 'That's a heck of a play.'
"He was a terrific, terrific player. He did a lot of damage as a defender when he was with the Patriots."
Fellow linebacker Gary Plummer was in his eighth pro season when Seau was a rookie in 1990, the No. 5 pick overall out of Southern California.
"He rejuvenated me. The fact he practiced 100 percent every day was something that I'll be forever grateful for," Plummer said.
One day, Seau asked Plummer if he wanted to join him in lifting weights at lunchtime before practice. At first he thought Seau was crazy, but then tried it. "That particular game I had a great game and felt fresh. I never missed a workout with Junior on Monday, Wednesday, Thursday and Friday.
"By the time we go out for game, you go out fresh. It was just a psychological thing: 'I didn't have to lift weights today.' It really helped. I played until I was 38 years old. I definitely give him some credit for that."
Ross said he recently sent a donation to Seau's foundation. About two weeks ago, he received a thank-you letter. Seau had signed it, and added, "Love you, Coach."
After Wednesday, the letter means so much more to Ross.
"Amen," he said. "I'm not going to ever let it get away. That was a very, very nice thing."