Britain's supermarkets are taking an ever increasing share of consumer sales, heightening the competition between close rivals such as Asda, Sainsbury's and Morrison's.
Currently 92.5 per cent of all groceries bought are from large chain stores, up 0.5 per cent on 12 weeks ago.
This should spell good news for supermarkets, but for retailers Asda and Kwik-Save, tough times lay ahead.
According to TNS Worldpanel grocery figures for the 12 weeks to April 23, Asda has just managed to secure the number two spot behind Tesco, with a 16.3 per cent share - unchanged on the previous quarter's figures.
But Asda's growth rate, although slightly above the sector average, is just three per cent, while third place Sainsbury's has enjoyed a five per cent sales growth in the same period.
Sainsbury's is 0.3 per cent behind Asda in total sales, with a 13 per cent market share.
This gap of 0.3 per cent has now been maintained over the last two periods, and reveals the intensity of the competition in the grocery market, said TNS.
TNS director Peter East told FoodandDrinkEurope.com: "I suspect the reality is that over the course of the year it is likely that Sainsbury's will take that second place spot. The interesting point will be how difficult or easy it is to hold onto this spot. It will be a close fight."
Meanwhile, sixth place Kwik-Save has seen a sharp decline of 34 per cent over the 12 week period, bringing its market share down from 1.8 per cent to 1.2 per cent.
TNS has attributed this to Somerfield's recent sell-off of the underperforming discount chain to the Tchenguiz entrepreneurial consortium.
Somerfield offloaded 171 of the 350 Kwik-Save stores to Back to the Future Ltd (BTTF) in February for a reported £200m.
BTTF head Niklas indicated the consortium will continue to operate Kwik-Save on a discount strategy, while building on its strong local presence. A convenience-style operation looks likely to be cemented over the coming months.
While this may not immediately improve TNS ratings for Kwik-Save, the move comes as discount retailers take a growing market share in the UK and across Europe.
Meanwhile Somerfield will concentrate on maintaining its fifth place position, converting 102 of the remaining Kwik-Save stores to the Somerfield banner later this year.
The firm currently holds a 4.1 per cent market share, but has enjoyed a four per cent growth in sales over recent weeks.
Tesco's results look stable, but subdued, according to TNS figures. Although growth levels are slower than last year, Britain's number one retailer is still leagues ahead with a 30.8 per cent market share and eight per cent sales growth rate - way above the 2.8 per cent industry average.