Pugh, explaining that the World Series helps players' development by allowing them to make errors at a top-class level, added: "We learnt some strong lessons, such as how hard it is to defend for long periods of time when you're without the ball, and not to give the ball away cheaply, which we did against Spain".
The New Zealand Black Ferns claimed the gold medal with a comfortable 26-14 victory over Canada in the final.
While Knewstubb was sin-binned in the second half, America finally scored but New Zealand prevailed 24-7.
Meanwhile in the women's series, world champion New Zealand remained flawless by beating Canada 26-14 in the final for a second title in this series and fifth straight going back to last season.
Sarah Goss, Michaela Blyde and Gayle Broughton each scored three tries as New Zealand posted Pool A victories over Kenya, Russia and Ireland on day one in Dubai on Thursday (Friday NZ Time), the second stop of the Women's World Sevens Series.
New Zealand were made to work harder in their 29-12 win over Russian Federation, with a first-half double from Goss and a second-half brace from Stacey Waaka getting them home after the match sat in the balance at 12-7 at halftime.
While watching the New Zealand and Kenya match, the live feed cut out.
Street by Saudi US embassy could be renamed 'Jamal Khashoggi Way'
In the video, the Saudi prince can be heard telling the French president "Don't worry", to which he replies, "I am anxious ". Saudi Arabia's public prosecutor has said the Crown Prince knew nothing of the operation to kill Khashoggi.
There was to be no first Dubai title for United States, though, as tries by Dylan Collier and Ngarohi McGarvey-Black ensured it would be New Zealand celebrating a long-awaited sixth Dubai title.
The Black Ferns Sevens will face Russian Federation in the first quarter-final of the Dubai Rugby Sevens at 6pm (NZT) after winning all their pool play matches on day one of the tournament.
It completes a double for New Zealand after the women won their event yesterday.
Canada finished ninth overall on the circuit last season. Of course, it has to be remembered that the team is in a rebuilding phase following the departure of several stalwarts, but they will be mightily disappointed with a sixth-place finish in Dubai.
Earlier, Samoa set up a Challenge Trophy final against France.
Meanwhile, the Canadian men went 1-2 in pool play Friday in the Dubai Sevens and will meet Zimbabwe on the consolation side today.