Who next for Morrisons? That’s the question on many people’s lips following chief executive Marc Bolland’s decision to take what must still be regarded as the top job in UK retailing – running the iconic Marks & Sparks.

The urbane 50-year-old Dutchman has more than proved his worth at the Bradford-based supermarket, ensuring that Morrisons is a force to be reckoned with in an intensely-competitive market sector.

Indeed, although it is the smallest of the Big Four – the others being Tesco, Sainsbury and Asda – Morrisons has consistently been winning market share from them for months.

Mr Bolland, who joined Morrisons from Dutch brewer Heineken in 2008, was little-known in the UK. Since then, by spearheading an overhaul of Morrison’s operations and putting fresh food at low prices through the in-store Market Street concept, he has differentiated the Bradford business from the pack.

The strategy may have been sound at any time, but in the recession it has proved to be spot-on. In its recent trading update covering the third quarter of 2009, Morrisons confirmed that it had continued to increase sales faster than its rivals, from whom it is also poaching customers. Sales grew by 9.1 per cent in the 13 weeks to November 1. This year Morrisons has recruited around 8,000 new staff.

Morrisons has added more than one million new customers over the past two years and plans to have a store within a 15-minute drive of every household in the UK.

Ironically, one of its key successes has been tempting more affluent food shoppers from M&S through Market Street, which employs more butchers, fishmongers and bakers than any other leading high street grocer.

Presumably, one of Mr Bolland’s tasks will be to reverse that trend.

Mr Bolland had a difficult act to follow. He was the first outsider to run the company, walking in the footsteps of Sir Ken Morrison, son of the founder, whose individual style and down-to-earth approach infuriated the City types but built a spectacularly successful business from its origins as a Victorian market stall.

Mr Bolland has succeeded in building on that legacy, making Morrisons even more successful after overcoming the effects of the difficult Safeway take-over in 2004, which caused Morrisons its first – and so far only – loss.

Despite denying his interest in the M&S job when announcing the half-year results in September, the lure of becoming boss of the UK’s most iconic retailer proved too much.

His departure from Morrisons will be seen as a major loss for the Bradford company, where his reign has been described by one commentator as a “triumph”.

He, in turn, has created a hard act to follow for his successor. But he is also leaving a business that is riding high.

We wait with baited breath for news of the new boss. The insider tipped to be the most likely successor is finance director Richard Pennycook.