Defending champions Fiji have shown they'll tolerate no revenge attempt from Wales for last year's agonising Cup final defeat, routing them 42-7 on the first night of the Hong Kong Sevens.
And New Zealand, who took to the field with something to prove after finishing fourth in the Tokyo round of the tournament last weekend, pounded Scotland 33-0.
But perhaps more ominous for Fiji was a 31-7 win by Series leader South Africa against France.
A tight Australia-Spain game saw the Aussies forced to batter their way through the Spanish defences to win the gruelling game 28-14.
England's James Rodwell, playing his 50th cap, scored one of England's three tries against old rivals Argentina, helping them to a hard-fought 19-12 victory.
The US, who impressed in Tokyo last week, came out fighting against a lacklustre Samoa, with the Eagles taking the game 26-12, while Canada put Portugal on notice with a 35-7 victory.
Kenya were merciless against Sri Lanka in the worst rout of the night, scoring six tries in 11 minutes, with an almost taunting seventh try coming at the death to seal Sri Lanka's fate 41-0.
The pool games continue on Saturday, with Fiji meeting Sri Lanka and Kenya, South Africa taking on Spain and Australia, and New Zealand facing Samoa and the US.
Meanwhile, the Cook Islands and American Samoa are in the qualifying tournament, of which the winner qualifies for next year's World Series as a full-time member.
The Cook Islands, in pool G, won both of their games, beating Uruguay and then Trinidad and Tobago.
American Samoa were beaten by Italy, and will next meet Tunisia.