With Chris Fusaro making a big impact last season, John found himself playing at six or eight for much of last term. But after impressing as a sub against Ulster, and getting the nod to start against Scarlets, the Scotland international is determined to keep hold of the number seven shirt.
John told the Evening Times: "I am an openside and I want to play seven. Chris had a great season last time and fair play to him for that, but that does not mean I am going to stand by and let him be the first choice.
"Being honest, my pride was hurt, however if anything it was probably the kick up the backside I had needed.
"I am not going to say I had been complacent, but I had been first pick, relatively unchallenged, at openside for several seasons before Chris's emergence last season.
"So I have had to look at my game and ask myself, has something dropped off and where do I need to improve? I have taken that on board and now I am determined to produce my best form and more this season."
John added: "Obviously you want to be playing and while I lost the openside berth I still got a lot of games and starts at either six or, on occasion, eight but these aren't my natural positions.
"So to be starting at openside tonight in our first-ever home game at the new Scotstoun Stadium is a massive moment for me. It is great to be back."