Davis netted a famous winner in this fixture back in 2009 in the rain, and having seen today’s pre-match conditions, the possibility of him grabbing a third Old Firm goal was posed to him.
He did just that on what was a poignant day for him and he told RangersTV: "We are delighted. We knew how important it was going into the game.
"Obviously, after having the league title success, I think it was a good game for us at this point in the season and it showed how much it meant to us out there today.
"Someone mentioned it before the game! It has been quite a while since I scored in an Old Firm, and I am delighted to get that one today.
"It is my mum's birthday today as well, and she has obviously passed away, and it is a nice memory for her as well."
Davis has scored many fantastic goals in his career, but an overhead kick was something new for him!
Asked if he’d netted like that before, he said: "Not outside of training! I don't think I score too many of them but it just sat up nicely - I'm not even quite sure what I was doing in the box at that time as I tend not to get that high up the pitch at times with the position I play.
"But it sat up nicely, I had a go, got a good connection and I wasn't sure if I was offside at the time, but luckily, it was an important goal for us.
"We were speaking about this the other day - every game is a big game at this club and it never changes, no matter what stage you are at in the season.
"So we knew how big it was being an Old Firm and the opportunity being to get to the next round of the cup, and after having that success, we want more of it and this was another step in the right direction for us."
Rangers had Allan McGregor to thank for keeping the clean sheet intact today, with the goalkeeper saving an Odsonne Edouard penalty late in the second half.
Davis said: "It was a great save and you cannot speak highly enough of him. He has had an outstanding season again and we all know how good he is.
"I don't think it was a penalty, but he was there to save it when called upon and he has been there for us many times this season."
Gers now face St Johnstone twice in the space of a week, firstly in the Premiership on Wednesday before in the Scottish Cup back at Ibrox next weekend.
Davis added on the Saints: "They are a team that are making good progress and it is going to be a difficult test for us over the two games - the league encounter and then the cup game.
"But it is one we look throughly look forward to. We will enjoy this one tonight, rest and get ready for Wednesday."
RangersTV subscribers can stay up to date with the latest RangersTV content wherever they are with the new improved app.
Once you have your subscription you can download the RangersTV app and watch every piece of content from our mobile device.
Download the RangersTV App from the links below: