Melville had one clear chance and veteran striker Marc Evans buried it from a free kick for a halftime lead.
Stand-in Tauranga keeper Daniel Thorby made a sharp save at the start of the second half but he was powerless to stop Evans scoring number two and Aaron Scott the third with barely an hour gone.
As Tauranga pushed forward to try and get back in the game there was more space exposed at the back which Melville gleefully capitalised on, scoring two late goals that on the run of play were hard on Tauranga City.
Still the younger Tauranga City players new to this level will have learnt more from this defeat than a season's worth of wins, which can only be a good thing as coach Barry Gardiner looks to build a stronger squad for next season.
"There were definitely signs of a better performance today but I am still not happy with the result. The first half we were very good. We had a game plan in how we wanted to approach the game and I think we did that very well," Gardiner said.
"It was disappointing to lose a goal just before halftime but it was a great finish from a free kick from Marc Evans. The last five minutes in the first half we were probably not quite at our best and again the first five minutes of the second half they scored again.
"When it gets to 2-0 the complexity of the game changes and you saw that in the second half. I think fatigue and tiredness came into it a little bit but I am really disappointed with the end scoreline."
The need to build more depth in the squad has been a high priority for Gardiner and against the better teams in the league is an absolute to compete.
"All year we have had concerns with injury. The squad's not been deep enough so when we have two or three players out you can actually see an effect of that.
"But full credit to the likes of DT (Thorby) who stood in as goalkeeper today. I thought he was very good in goal."