"I shed a few tears before the game, I shed a few during the game and I shed a few after," Berry said. "There were a lot of emotions, but I tried to contain them and let everything show through my play."
Berry, who beat Hodgkin's lymphoma, had a 37-yard interception return for a touchdown shortly before halftime, then picked off an attempted conversion pass in the fourth quarter and raced 99 yards for the decisive two points in the Chiefs' 29-28 victory over the Atlanta Falcons.
"The last time I came home during the season it was to get chemotherapy," Berry said. "This time it was to play a game, so I was thankful for the opportunity. I take pride in a lot of things people take for granted. I cherish everything that comes my way."
After his touchdown, Berry raced to the stands and gave the ball on his mother.
"I made up my mind before the game that I was going to give her a ball," the All-Pro said. "It won't amount to the things she has given me, and my dad as well. So many nights I was crying on their shoulders and trying to make sense of everything that was going on.
"They kept telling me, 'Keep pressing, you'll be back.' They helped me through the whole process. I can't thank them enough. ... I love them. I'm just thankful they could come to the game and see me play."
Berry, the fifth overall pick in the 2010 draft out of Tennessee, was diagnosed with cancer about midway through the 2014 season, but was healthy enough to return last year.
The touchdown return was his second of the season, and he has three interceptions plus the decisive two-point turnaround against the Falcons.
"I was just reading my keys. A lot of film study," Berry said of stepping in front of Taylor Gabriel and turning Matt Ryan's pass into six points for the Chiefs just before halftime. "I put in a lot of time, then trust my instincts."
"That was a good play by Eric and a decision that I can't make," Ryan said. "I've got to check the ball down or move on."
The two-point return, when Ryan was trying to hit rookie tight end Austin Hooper, came just after the Falcons had taken the lead.
"I expected a combination coverage to the outside and Eric Berry did a good job of coming down on the tight end," Ryan said.
"Growing up, my dad always told me the most important point of the game is the extra point," Berry said. "A lot of people take that play off, but it was an opportunity to make something happen and I was going to make the most of it."
The victory gave the Chiefs a 9-3 record and kept them in the chase for the AFC West title.
"Atlanta's a good team. ...We just wanted to come out and show that we were a good team as well," Berry said.
With a big assist from Berry, the Chiefs did just that.
"Just think, a year or two ago he had cancer and he had to battle through that," linebacker Tamba Hali said. "You don't get any better than Eric. He's an All-Pro and a leader. He doesn't talk about how good he is, he just goes out and shows it."