Isaac Kay did what was necessary.

He grabbed the loose ball and booted it high into the Hong Kong crowd.

Game over. Game won.

Kay did not jump for joy. Nor did he high-five any teammates, or punch the air in celebration. As the referee's whistle blew to confirm Kay's action was the final act, he simply squatted and shook his head.

He knew what we all knew. It was another missed opportunity for Canada.

Yes, Canada had won – but it was a hollow victory. Beating Portugal – a team of largely inexperienced youngsters, was the bare minimum expectation at the historic Hong Kong Sevens.

WATCH | Canada vs. Portugal:

Watch Canada take on Portugal at the World Rugby Sevens Series in Hong Kong. 19:20

It wasn't even a convincing win. In the event it was irrelevant since Canada's fate was sealed before a ball was kicked. Losses to Argentina and France had already consigned them to another day of consolation Challenge Cup hard labour.

Canada is not a team that could. Canada is a team that can. It has teased us with glimpses of brilliance; less than a month ago it had the audacity to beat Fiji, the Olympic champions. Canada is a team that can, but too often does not.

In Hong Kong, the team struggled to overcome the part-time Portuguese. There is a reason Portugal lost its core status three years ago. It is not good enough to compete at this level of rugby sevens. Yet it threatened to embarrass the Canadians, and certainly got much too close for comfort.

Canada has only itself to blame. These are self-inflicted wounds. Rugby sevens is a simple game where pace and possession is paramount. Any aspiring nation must be able to protect the football and act quickly. Canada is guilty of not executing the basics well enough.

WATCH | Canada vs. Kenya:

Watch Canada take on Kenya in the Challenge Trophy Quarters at the World Rugby Sevens Series in Hong Kong. 21:29

The talent exists. The Canadians may not have the production line luxury enjoyed by the likes of New Zealand, Fiji or South Africa, but it has top level players. Most teams would roll out the red carpet to welcome the likes of Nathan Hirayama, Connor Braid or Justin Douglas.

But it is not about individuals. Just look South. The Americans have a global superstar in Perry Baker – or rather they did. Baker – the reigning World Sevens Player of the Year – has played only a handful of game this season due to injury, but the Americans are better than ever. It is, and always has been a team game, and as a team, Canada is too often found wanting.

Talking of Team U.S.A., the Canadians should go to bed every night singing the Stars & Stripes. The Americans' continued series success is almost certain to lead to an automatic Olympic berth. Canada's regional qualifying campaign should therefore be somewhat less daunting without the U.S. to obstruct the view.

The Americans enjoyed another strong weekend. They again reached the podium – their sixth in seven outings to remain top of the series standings. Fiji closed the gap, victorious in Hong Kong for the fifth straight year, registering their third win of the season.

WATCH | Fiji battles France for gold:

Watch Fiji and France battle in the Cup Final at the World Rugby Sevens Series in Hong Kong. 44:28

Meanwhile, Canada plods on, playing for scraps to preserve its own core status. At a time when some could do with a rest before next month's qualifiers, they are still required to show up game in, game out to prevent any dramatic decline in the closing three tournaments.

WATCH | Canada vs. Wales:

Watch Canada battle it out with Wales in the 13th place semi at the World Rugby Sevens Series in Hong Kong. 22:05

No excuses from Coach Damian McGrath. After his team capitulated to Kenya and then Wales, finishing last, he admitted it "was without doubt the worst tournament we've played since I began coaching Canada 7s." Full marks for honesty.

It is a short hop from Hong Kong to Singapore. Two short years ago, the Canadians celebrated the greatest moment in their sevens history, climbing the mountain and winning the Singapore tournament in a thriller against the Americans.

Isaac Kay was on the field on that humid, glorious night in Singapore. He knows what it takes to win all the marbles. Little wonder he shook his head in Hong Kong.