The stopper replaced the injured John Souttar beside Ben Davies in the heart of the defence in the 5-2 win over Dundee.
Philippe Clement’s men were 2-0 down to the visitors, with King believing he should have done better for both strikes.
He redeemed himself by getting an assist as Ross McCausland reduced the deficit before half-time.
Second half goals from Cyriel Dessers, Todd Cantwell and a brace from Scott Wright secured the three points in the final home game of the season.
King was thrilled to be back in the side and insists a pre-match pep talk from the gaffer paid off.
Speaking to RangersTV, he said: “It was good in the end. We started the game well but then we gave them two easy goals which we could have done a lot better with, especially myself.
“I probably take the blame for the first goal as it was a mix up between myself and Ridvan at the back post.
“We bounced back well and had a great second half.
“The fans deserved goals and the three points and it was nice to get back to winning ways.
“It was brilliant to make my first start in a year.
“The gaffer said he wanted me to do what I had been doing in training and I would be fine. It was great to get that confidence booster.
“I am learning every day and I love every minute of being here and I wouldn't want to be anywhere else.”
Rangers travel to Tynecastle to face Hearts in the final Premiership encounter of the season on Saturday before the Scottish Gas Scottish Cup final against Celtic on May 25.
King says it was vital the squad put the weekend derby defeat behind them quickly as they look to end the campaign with two trophies.
He added: “We have to try to build momentum ahead of the massive game that is the cup final.
“We want to go into that game with confidence and hopefully end the season on a high.”