We all know competition is fierce, but it’s amazing what a lamb chop promo can do for a supermarket’s performance.

With Asda’s price on the chops up 62.1%, after a one-week promotion, Morrisons walked away with the prize, with a gap of £6.25 compared with only 26p last week.

To be fair, it wasn’t just the chops, which were down by £1.73 per kg.

With 16 of the 33 cheapest items, including reductions on Dairylea spread by 11p, Jacob’s Creek by 31p and Patak’s by 1p, Morrisons was easily the cheapest.

Asda lagged behind Morrisons, despite matching or being the cheapest on 21 of the 33 items. The retailer had significant promotions on Birds Eye cod, down 56p, cauliflower, down 25p, lemons (10p) and oranges (9p).

The second-placed retailer had just two price hikes, with the lamb chops up by £4.97 per kg, and salami up 16p.

It was a better week for Tesco, which rose to third place, though it could have come second if it had been just 8p cheaper.

A promotion on Jacob’s Creek ended so it went up by £1.43, but there were significant price reductions on Frozen Fruits of the Forest by (down by 70p) and smoothies (down by 9p).

Sainsbury’s slipped to fourth place this week, but undercut Waitrose by a massive £6.58. The retailer had just one small price hike on mature Cheddar slices – 2p up – and several significant price reductions. White seedless grapes were on promotion, down by £1, German salami was down 40p, and lemons 5p.

Waitrose once again proved to be the most expensive retailer, coming a distant fifth place.

But although the retailer had 29 out of the 33 most expensive items, it boasted four price reductions and zero price hikes.

Frijj Classic shakes were down 8p, German salami was down 53p, Jaffa Cakes by 3p and smoothies down by 54p.