The late good ol’ Sam Walton, driven by his three cardinal rules for business-building, has elbowed his way into the number two slot in Britain’s supermarket league.

Wal-Mart’s UK acquisition Asda, for long number three among the UK’s Big Four chains, has overtaken J Sainsbury by snatching 17% of the market in the four weeks to July 20. This compares with Sainsbury’s 16.2% but is ten percentage points behind market leader Tesco which commands a 27% slice of the cake.

Sainsbury attempted to make light of its relegation, pointing out that the sales data (from TNS) included revenues from Asda’s highly successful George clothing brand and that, in purely grocery terms, it remains runner-up in the league.

But TNS numbers show that Sainsbury has been losing market share over the past six years. Observes Credit Agricole food analyst Mike Dennis: “This is a reflection that Sainsbury has lost penetration in UK households. Sainsbury is stuck in the middle ground. It is neither a high-end retailer like Waitrose, nor a volume retailer.”

Or might it be that Sainsbury overlooked Sam’s three golden rules?

1. Respect for the Individual.
2. Service to Our Customers.
2. Strive for Excellence.

Data sourced from: Financial Times; additional content by WARC staff