Perry Baker scored a brace as USA brought the curtain down on a scintillating day of Rugby World Cup Sevens 2018 action at AT&T Park with a 35-0 defeat of Wales to take their place in the Championship quarter-finals.

The hosts are joined in the race for the Melrose Cup by defending champions New Zealand, Olympic champions Fiji, HSBC World Rugby Sevens Series 2018 winners South Africa, RWC Sevens 2013 runners-up England, Argentina, France and Scotland.

The Championship quarter-finals will get underway at 15:32 local time (GMT-7) on Saturday with Scotland facing South Africa, Argentina taking on Fiji, France meeting New Zealand and USA tackling England.  

VIEW MEN's #RWC7S FIXTURES AND RESULTS >>

The men’s tournament began with a preliminary round featuring the nations ranked ninth to 24th to determine who would progress to face the top eight seeds in the round of 16 and who would take their place in the Bowl bracket on the final two days of the tournament.

Highlights: Men's first session
It's been all go in San Francisco during the first round of 16 at Rugby World Cup Sevens

Papua New Guinea, making their RWC Sevens debut, came close to upsetting the form book when the 23rd seeds battled back from 24-7 down against Canada with some slick handling and pace leading to tries by Henry Kalua and Hensley Peter. There was to be no fairytale comeback, though, with Connor Braid making certain of a 29-21 victory for Canada.

Chile and Ireland were also involved in an epic battle that went down to the wire. Ireland, winners of a bronze medal in the London round of the series, looked to be heading for extra-time against the battling South Americans until they worked Jimmy O'Brien over in the corner with time up, much to the relief of the Irish fans in the stands.

The drama continued into the round of 16 with an incredible comeback by Scotland to beat Kenya 31-26. The eighth seeds had trailed 26-0 against the Kenyans, who had battled past Tonga 19-7 in their opening match, but five second-half tries to the delight of the AT&T Park crowd. Scotland made the most of the space created by Belgium Tuatagaloa's sending off for two yellow cards to storm back, captain Scott Riddell coolly sending Jamie Farndale over for the winner.

Argentina's 28-0 victory over Canada was more straightforward before the drama continued as France shocked Australia. With two and a half minutes to go the scores were level at 17-17 before Les Bleus found Tavite Veredamu in space out wide and he had too much pace and power for Australia.

The reward for France is a Championship quarter-final with defending champions New Zealand. The All Blacks Sevens beat Russia 29-5 to signal their intentions to become the first nation to win back-to-back tournaments. They led 12-5 at half-time but quickly built on that with Joe Ravouvou a constant threat with his physicality and speed. 

Fiji endured an intense battle with Japan to start their bid for a third RWC Sevens title and went in at half-time trailing the Asian champions 10-7. However, the footwork of captain Jerry Tuwai, one of five Olympic gold medallists in San Francisco, ignited the Fijian attack and three quick-fire tries from Josua Tuisova, Semi Radradra and Jasa Veremalua helped wrap up a 35-10 win.

South Africa faced no such problems against Ireland with Siviwe Soyizwapi becoming the first player since RWC Sevens 2005 to score four tries in a match in their emphatic 45-7 victory. That left the hosts to bring the curtain down on day one and, drawing on the euphoria of the crowd, they ran out 35-0 winners with captain Madison Hughes converting all five of their tries.  

The Bowl quarter-finals kick-off the men's action on Saturday involving the teams that lost in the preliminary round of matches. 

Follow all of the day two action at rwcsevens.com, the RWC Sevens App or via @WorldRugby7s using #RWC7s.