The 18-year-old centre came off the bench in the second half to help England's up-and-coming stars hit a half-century against the Azzurri. The result not only sent the 7,945-strong crowd home happy, but also put England within striking range of the Six Nations title, and a win over Wales next weekend would see Stephenson and his team mates lift the trophy.
But while Stephenson says that the result was what the squad wanted the performance will have to improve against the Welsh, whose own win over Scotland means they are now chasing a Grand Slam themselves.
"First and foremost it was great to get the win," he said. "Italy was always going to be a fairly hard game; I think that's the biggest scoreline against them in this Six Nations.
"However it wasn't the performance that we were looking for and we'll have step up against Wales next week if we're going to win that game and win the Six Nations.
"Our intent was good, but the conditions were slippy and we maybe tried to force the offloads and made handling mistakes. In the second half we picked up our intensity.
"It was a great crowd here. We'd been told it was going to be a big crowd and it was. And I certainly wasn't expecting to get a try. If you saw the smile on my face when I scored it that would have said everything. I don't get too many tries, so when I do I enjoy them!
"Credit to the forwards, too, who made our job a lot easier."
Stephenson was one of four members of the Saints Senior Academy to represent England Under-20 on home turf. Danny Hobbs-Awoyemi put in a strong performance in the tight and the loose from the start, while Danny Herriott came off the bench to help the pack earn two second half tries. Alex Day also came off the bench in the second half, and with all four receiving loud receptions from the stands there was as much good feeling in the crowd as there was between the players themselves.
"I said earlier in the week that playing with the boys you train with every day at Saints and then stepping into the international scene is pretty good," Stephenson added. "We've known each other for four or five years and to pull on the white shirt together is a great experience."