He is the chief operating officer of a retail empire that dominates high street fashion, but Ian Grabiner is still a relative unknown.

As Sir Philip Green, Arcadia’s owner, excused himself from a lunchtime meeting to address 200 staff, Mr Grabiner slipped in to introduce himself to reporters yesterday. Such is life in the shadow of Sir Philip. It is an arrangement that appears to suit both men. The banter between the pair suggests a complementary working relationship.

“He always likes to say he runs the place,” Mr Grabiner joked, with a nod to Sir Philip across the table.

Mr Grabiner looks after Arcadia on a day-to-day basis, but is far more than a behind-the-scenes stagehand. The 48-year-old has form in the rag trade: his father and uncle ran a clothes company and his first job was working for River Island in the early 1980s. His working relationship with Sir Philip stretches back 20 years.

He worked under the entrepreneur in the late 1980s and early 1990s as managing director of What Everyone Wants, the now-defunct Scottish discount subsidiary of Amber Day, the retail group led by Sir Philip. After Sir Philip was ousted as chairman and chief executive, he left and worked for Littlewoods in Northern Ireland.

In the late 1990s, Mr Grabiner worked under Sir Tom Hunter at Sports Division, alongside Chris Ronnie, now the chief executive of JJB Sports. In 2000, he made nearly £2 million when Reality, an e-commerce company in which he had a 20 per cent stake, was sold to Great Universal Stores. Sir Tom also had a 20 per cent holding.

It was through Mr Grabiner that Sir Philip met Sir Tom, who invested in the former’s raid on Sears, the British retailer. Sir Philip made huge profits from the eventual break-up of the group.

Mr Grabiner stayed on at the enlarged Reality Group until 2002. His 2.5 per cent stake in Taveta Investments, Sir Philip’s holding company, was enough to propel him into the Sunday Times Scottish Rich List. Mr Grabiner took the helm at Arcadia only three months after Sir Philip’s purchase in 2002, replacing Stuart Rose, now Marks & Spencer’s executive chairman.

Although Mr Grabiner’s face may not be familiar, his surname may well be. He is the first cousin of Lord Grabiner, one of the country’s leading commercial barristers and a former chairman of Arcadia. Stephen Grabiner, the head of private equity company Apax, is another cousin.