The four-time light welterweight national champion dropped the Australian with a body shot in the first round in a qualifying bout.
Speaking to the Otago Daily Times from Auckland, he said it was a strong performance.
"I knew he would be a slick boxer and the game plan was to stay on him but be aware, and use boxing skill to get in and out of range. I achieved that really well."
He admitted Demirkaya came back strongly in the second, with large shots and good movement. But despite Hadlow receiving a few blows, coach Stewart Mitchell said it was one of his best performances.
"We knew this kid was tricky hands-down style with great balance and movement, so Richie had to really slowly turn the screw, making him move and burn a lot of energy ... keeping his punches sharp.
"Richie boxed superbly ... securing a fantastic win and now opening the door to some fantastic opportunities."
However, the local lad has to wait for the rubber stamp to know if he has been granted his Commonwealth spot.
"It now becomes a waiting game for the five places to be confirmed but the reality is Richie is one of three boxers who have met all the criteria laid out over the past 12 months, so should have qualified with some wriggle room," Mitchell said.
Next up for Hadlow is an international training camp in Colorado with Team GB, Ireland and Poland next month.
While he taking nothing for granted, he is confident in his performance and said the training camp would boost his skill level and abilities in the ring.
