Olympic champions Fiji launched the defence of their USA Sevens crown in style, thrashing Japan before overpowering Scotland to remain on course for the quarter-finals.
The Fijians, who are still without a tournament win in this season's World Sevens Series, looked like a team on a mission with a ruthless 41-0 demolition of Japan in their opening Pool D game at the Sam Boyd Stadium.
The 2016 Rio de Janeiro gold medallists then followed that up with a 24-12 victory over Scotland in their second game.
The Scots had earlier finished on the losing side in the best game of Friday's opening matches, losing 28-21 to Australia in a thrilling duel.
Scotland had looked to be on course for a deserved win after surging into a 21-7 second half lead.
But two tries from Lachie Anderson helped Australia draw level before skipper Ed Jenkins came up with the decisive score on the whistle.
Elsewhere Friday, series leaders South Africa were made to work hard by a physical Canada side in a 26-7 win.
The Blitzboks, who have won tournaments in Dubai, Wellington and Sydney this season, were then too strong for France in the final match of the night, winning 31-0.
New Zealand meanwhile failed to impress in their opening games against Kenya and Russia.
The Kiwis trailed 5-7 against the Kenyans at half-time before grinding down their opponents in the second half to win 24-7.
The New Zealanders also struggled to convince against Russia, making hard of subduing the physical European minnows before running out 19-5 winners.
In Pool B, the United States and England are on a collision course after opening wins that set up a group decider on Saturday.
The USA opened with an emphatic 26-5 win over Samoa, Danny Barrett scoring a fine hat-trick as the South Pacific Islanders struggled to cope with the Americans speed and tempo.
The US then swatted Chile 31-0 to set up a showdown with England, who also won their opening games. England downed Chile 31-5 but were pushed hard by Samoa, hanging on for a 12-5 win.