Saints claimed one win from three games on the first day of the World Club 7s at Twickenham.
Pool B clashes with Buenos Aires and San Francisco went by without much to smile about, but Tom Stephenson’s two-try salvo ensured Blue Bulls were beaten in the third game.
Saints had failed to win a single match in the recent JP Morgan 7s tournament at Franklin’s Gardens, but they fared better at English rugby HQ.
Their team, again a mix of youth and experience, were blown away by a Buenos Aires in the opening game, shipping six tries in a 30-0 defeat.
Saints struggled to get out of their own half for the entirety of the encounter, going behind in the first minute to Juan Ignacio Brex’s score in the corner.
Brex got his second try soon after and Buenos Aires captain Lucas Alcacer also registered before the break.
Saints got their hands on the ball a bit more at the start of the second period, but again the Argentinians dominated proceedings.
And Matias Moroni, Gonzalo Guttierrez Taboada and Mariano Zinani all added their names to the scoresheet to complete the rout.
Next up for Saints was a San Francisco side containing the man touted as the fastest player in world rugby, American speedster Carlin Isles.
Isles had helped his team to a 28-19 win against Blue Bulls and was in superb form as they went on to make it two victories from as many games.
Northampton had been all over their opponents from across the Atlantic early on, with Tom Collins just unable to latch on to a cheeky grubber kick.
But Saints were hit with a sucker punch before the break as the ball found its way to Isles, who didn’t even need to get out of second gear to score.
Isles was at it again after the interval, but this time he did step on the gas, flying around the side of Saints’ defence to give himself a clear run home.
But Collins has plenty of pace of his own and after jinking past a couple of challenges, he touched down to give his team their first points of the tournament.
Academy player Ollie Lyons then helped level the scores, showing determination to register before Harry Mallinder made the conversion.
But Isles, who looked like he could score at will, made sure of the victory for San Francisco, again turning on the turbos to secure a 17-12 success.
Saints were desperate to end the day with a win, and they got it thanks to Stephens
The England Under 20s centre opened the scoring against Blue Bulls, before Lyons added a second to put Saints 12-0 up.
Bulls replied through Ezequiel Valy, but Stephenson had the final say, diving over in the corner to ensure his side had a spring in their step ahead of the following day’s action.