Conlan appeared a class above Ruiz for most of the 10 round contest
Michael Conlan cruised to his 12th professional win as he outclassed Diego Alberto Ruiz in front of a raucous crowd at Falls Park.
Conlan's dominance was rewarded in the ninth round when, after a flurry of body shots, the contest was stopped.
Ruiz, in his first bout outside his native Argentina, failed to challenge Conlan's superiority at any stage.
Conlan will now seek a step-up in terms of opposition as he works towards a world title shot.
In front of 10,000 fans in west Belfast, just a stone's throw away from Conlan's childhood home, the former Olympian delivered a performance of suitable skill to suggest that there will be bigger nights ahead in the near future.
However, as Conlan's trainer Adam Booth suggested after the contest, tougher tests are undoubtedly to come.
"I know I am not the biggest puncher in the world but I have enough to make people respect me," said Conlan.
"I know I can beat anybody when I box but I know people get bored of that.
"I maybe should do it all the time because the less damage you take in the ring the more life you get in boxing, but I know these fans wanted the finish and I'm happy I gave the fans that."
Blood, sweat and tears - Conlan savours Falls Park win
A low key opening allowed Conlan to ease himself into the ascendancy, regularly switching between the orthodox and southpaw stances with Ruiz offering little in terms of attack.
In the fourth an accurate left landed on Ruiz's chin to prompt a swell in noise around the now rain-soaked venue.
A right hand four rounds later again brought the crowd to their feet as Conlan sensed a stoppage was on the horizon.
Indeed the referee's intervention arrived in the ninth with Ruiz, forced to take a knee after a right to the body, was unable to protect himself adequately as Conlan came forward.
"He need's to feed that nastiness" - what they said
Michael Conlan's coach Adam Booth: "He is now showing things with the 8oz gloves on that he is doing in the gym.
"His jab was actually working a bit too effectively because the jab was keeping Ruiz at bay but it was also keeping Michael at bay.
"He needed a finish like that as well and I genuinely think that's his best performance yet. He needs to feed that nastiness. Yes, he can outbox dudes but this is the professional fight game and you need to be able to hurt them and get rid of them."
Former world flyweight champion Dave 'Boy' McAuley: "Michael Conlan will be world champion at some stage, but I believe looking to next year is too soon. He has had too few fights and he hasn't got enough experience yet in my opinion.
"It's 18 months down the line in my opinion. Tonight was a top-notch performance and he did very well. He got rid of a slippery opponent but you take the likes of Santa Cruz, Gary Russell and Warrington. Conlan will get there, but personally I think it's too soon."
