Fenton laced up his boots for his first A-League appearance but former Belgian international Stein Huysegems has been a professional since he was 16 and has clocked up more than 300 games in 14 years of top-level football.
Fenton, who still lives at home in Wellington suburb Tawa, is one of two graduates from the club's inaugural intake to their school of excellence.
The 30-year-old Huysegems came to the capital highly regarded after fruitful spells in the Belgian and Dutch first divisions.
Huysegems' finish was well-taken and showed he has the touch, time and temperament to be a force in the league.
Fenton's diving header in the 75th minute was the stuff dreams are made of for a young man who admitted he got only one night's good sleep in the week leading up to the game.
Phoenix fan club the Yellow Fever love nothing more than finding a new hero to rally behind and Fenton made a beeline for the supporters after his header found the back of the net.
"I didn't know where I was running, just all emotion. I didn't know what was happening, to be fair," he smiled.
As for the goal, the typically under-stated teenager offered this: "Just a great ball from Manny and I kind of just ran on to it and it hit my head and went in, I didn't know too much about it really.
"This is only the start hopefully and I have to keep getting better and improving every game."
Benjamin Totori and Jeremy Brockie also made their starting debuts for the Phoenix and Tyler Boyd and Ricardo Clarke also came from the bench to register their first official appearance in yellow and black.
Totori was direct on attack and showed no fear in running at defenders but might need to work on staying on his feet more as the right winger fell over at the slightest touch from a Sydney defender.
He could have taken notes from Del Piero, who said he was impressed with what the Phoenix produced.
"All the Wellington [players] played a very good match," Del Piero said. "They are strong and they play good every ball. They have ideas. Congratulations to the Phoenix and we see next game."
The Phoenix made the perfect start to their A-league season but face a tough trip to Melbourne Heart next weekend, made more difficult by the fact they will be shorn of seven All Whites and Solomon Islands international Totori who are all on international duty.