With the kick-off almost upon us, leading brands are going head-to-head in the supermarket, fighting for the extra sales that comes from leveraging interest in the 2010 World Cup and the goodwill associated with the Socceroos.

On closer inspection, though, not every brand wearing green and gold or a soccer motif is actually on the official FIFA or Football Australia squads. Just as the World Cup comes around every four years, so too — inevitably — does the potential for ambush marketing.

In the soft drink aisle, Coca-Cola is taking full advantage of its status as a global FIFA partner. Most Coke products have been repackaged to carry clear references to the World Cup and South Africa, and there are prominent local promotions and competitions under the banner “Bring Home the Celebration”.

But Coke doesn’t have the soft drink category all to itself. It’s facing strong defence from Schweppes Australia’s Solo brand. The reason there’s no mention of the Socceroos and no green and gold on Coke products is that Solo is “Official Non-Alcoholic Beverage Partner of the FFA, Qantas Socceroos, Westfield Matildas and Schools 5-a-side Program”.

Solo has been running soccer-related promotions since August 2009, first under the banner of “Game On”  and now culminating in the quirky Solo Lucky Undies.

As an official FFA partner, Solo is allowed to use the FFA and Socceroos names and logos, and to show Harry Kewell wearing a Socceroos uniform in Solo ads and even on Solo packaging.

Look — there’s Kewell in the cereal aisle, too. But this time he’s not in a Socceroos strip. In fact, two major cereal brands — both of which leverage sporting activities heavily in their promotion — are going head to head in a rivalry that actually sees one Socceroo pitched against another.

Kewell occupies the entire front face of the packaging of Kellogg’s Nutri-Grain, and is the centerpiece of a competition timed to coincide with the World Cup. Nutri-Grain packs carry big splashes of gold on the front and back and text that shouts: “Win your place in Kewell’s Football Boot Camp“.

But there’s no reference to the World Cup or even to Kewell’s past appearances as a Socceroo. Instead, he’s described non-specifically as a “legend” and wears a neutral Nutri-Grain shirt.

Kellogg’s competitor Sanitarium Weet-Bix, by contrast, is festooned with official sporting logos and proudly announces itself as “Official Breakfast of the Qantas Socceroos”. There are prominent pictures of “Qantas Socceroo Tim Cahill” in full uniform and a promotion for the Weet-Bix website, which has more pictures of Cahill and an invitation to join “Tim’s Tribe”. There’s even a special, limited edition, commemorative Weet-Bix tin.

Over by the confectionery section, there’s a stand-alone display too big to fit in the regular aisle. Mars Incorporated’s M&M’s brand is running a promotion that features specially packaged green and gold M&Ms and a giveaway of thousands of free “M-Balls”. The surface of the “M-Ball” features the classic pattern of hexagons and pentagons so distinctive of a soccer ball, although the ball itself is egg-shaped.

So … green and gold and a soccer motif but no actual reference to Australia, soccer, Socceroos, or the World Cup.

Are marketers who use soccer references at the time of the World Cup engaging in ambush marketing? The lack of direct reference to the World Cup, or the absence of an “official” sponsor in their category are often given as reasons for why such conduct is NOT ambush.

But contemporary definitions of ambush marketing have broadened to encompass any effort by a brand to associate itself with an event in order to reap the same sort of benefits that an official sponsor would enjoy — benefits such as consumer attention, attraction and positive sentiment. And these definitions don’t depend on a direct competitor or “official” sponsor being disadvantaged: sporting bodies often see such free riding as undermining the price they can command for official sponsorships in the future.

We asked Football Australia to respond to several questions about sponsorship and its attitude to the “unofficial” use of football imagery and even Socceroos players. But all of the relevant marketing or corporate affairs people, we were told, are already in South Africa and (apparently) too busy to reply.

Mars Incorporated has been an innovative sponsor of Australian sport in the past, responsible for the Carlton AFL team playing in light blue jumpers to launch a new M&Ms colour, and for Geelong Cats player Garry Hocking changing his name by deed poll to Whiskas for a single game, a move that attracted international attention. But contacted through its lawyers this week, Mars Incorporated had no official comment on its green and gold M-Ball promotion.

And, as they snack on M&Ms or a bowl of Nutri-Grain while watching the World Cup action in the early hours, it’s unlikely that many consumers will stop to ask whether these are official World Cup munchies.