The 34-year-old made his first appearance of the season in the Championship on Saturday when he started the game against Brighton & Hove Albion away from home.
Collins played a key role in the match at The Amex, scoring the equaliser for the visitors just before half time.
After the game which ended in a 3-2 victory for Forest, the former Sunderland and Stoke City star spoke of his gratitude for new manager Freedman.
“I’m obviously delighted that Dougie’s given me the chance today to come in and be part of a winning team,” he told Forest’s official website. “To cap it off with a goal was special.
“It’s been frustrating. You train all week and you want to be part of it on a Saturday. It’s been a disappointing five or six months but I’ve stuck at it, worked hard and hoped my chance comes.”
Collins played the entire 90 minutes, but he probably should have done better overall as Forest conceded twice.
The former Wales international had a pass accuracy of just 62%, although he won 67% of the duels.
However, the win at Brighton is only going to boost the confidence of Collins and the rest of the Forest players.
The Nottingham-based club are currently 12th in the Championship table with 37 points from 29 matches, 10 points above the relegation zone and 13 points behind sixth-placed Watford.