Karen Earl is curled up on her sofa, glass of white wine in one hand, mobile phone in the other as she studies each twirl and turn. A samba elicits a raised eyebrow and a furious session of texting to a friend; another hip-wiggling disaster produces merely a bout of mirth.

“I really just want to be there in the studio,” she says. “I have never had the chance to go, but every Saturday night when Strictly is on, I wish I was at those ringside seats getting some of the atmosphere. It is a wonderful show.”

Millions agree. For all those who say that they relax with their hobbies, the rock climbers, wood turners and saxophone players, the fact is that come Saturday night many, many more will unwind in front of the telly, losing themselves in the spins, sequins and celebrities of Strictly Come Dancing.

Ms Earl knows her Strictly and her expert eyes do not rate the chances of Phil Tufnell, the former England cricketer, pulling off something of a unique hat-trick for his sport, following Darren Gough and Mark Ramprakash as a Strictly champion.

But she knows her cricket, too. She is that rarest of rare things, a woman who is a big-hitter in sport, still dominated by blazers even in the 21st century, whose voice matters in a £1 billion industry. As chairman of Synergy, a consultancy with a roster of blue-chip businesses whose names are as familiar in football stadiums as in the high street, she is one of the most powerful figures in the sponsorship industry.

Sports sponsorship has suffered a bad press of late as the downturn and big losses in banks and multinationals have led pundits to seek scapegoats. They were there in spades — such as Sir Fred Goodwin, the disgraced Royal Bank of Scotland chief executive, whose spending on sports sponsorships made him an easy target. Here was a bank that paid already wealthy sportsmen and women, the likes of Andy Murray, Zara Phillips, Jack Nicklaus and Sir Jackie Stewart, millions to be RBS ambassadors. It tied up a £20 million deal to sponsor Rugby Union’s Six Nations Championship, just days after announcing a record £28 billion loss. And, at the same time, it had its name plastered all over the side of a car in Formula One, that most ostentatious of sports.

As criticism turned to insult and Sir Fred headed for the exit, the bank’s new bosses reached for the axe and took a swipe at the entire sponsorship budget, promising to halve it by next year. Ms Earl winced more than once, because her Synergy business was behind a lot of the RBS strategy to raise its profile through sport.

She is also unmoved by the critics and mounts a reasoned case for Sir Fred and RBS: “RBS proved, in a perverse way, that their sponsorship deals were justified. The criticism of the sponsorships was largely because it was so high-profile.

“Sir Fred had the vision that if he wanted his brand [to go] global, attaching it to global sponsorships would work better than anything else. So you could say it was a visionary decision. A few years ago, RBS was a little Scottish bank, but he believed it could be global. To go from local to global sponsorship was a very good vehicle.”

From the austere, but spendthrift, Sir Fred to the blonde Ali Bastian — a star of a soap that neither Ms Earl nor I have seen — who sweeps across the television screen clinging to Brian Fortuna, her American professional dancer, and gains a murmur of approval. “She looks good,” Ms Earl says. “Probably better than Tuffers. Oh dear, those super-wiggly hips and feet everywhere. I can’t resist that grin, though.”

There is a special affection for cricketers here, probably because they were the sportsmen she worked with first. Ms Earl grew up in Newmarket, inevitably around horses, the daughter of a sports-mad father and a mother who couldn’t tell a bat from an oar. She rode, though not well enough to take it up as a sport, and had no idea where her career would go. She went to a secretarial college and, in 1969, drifted into public relations “because it sounded glamorous”.

After spells as a PA in the City, she went on holiday to rethink her future and returned to a job at the Sports Council. There she was immersed in sport and enchanted by Sir Roger Bannister, the world’s first four-minute miler and the organisation’s first chairman, typing his speeches in super-large type so that he could read them.

But she was restless and luck intervened when she asked for a job at West Nally, one of the pioneers of sports sponsorship. Peter West was the quintessentially English cricket commentator, whose business partner, Patrick Nally, was the driving force behind deals that have formed a template for sponsorship agencies today. Their agency came up with the simple, much-copied idea of putting sponsors’ logos on stumps.

“It turned out to be working on the Benson & Hedges Cup cricket account as the secretary. I didn’t know much about cricket when I started. A year later, I still didn’t know much about cricket, but I knew a lot of people.”

The combination of Nally’s nous and West’s charm was formidable. West talked Cecil Burrows, general manager of Cornhill Insurance, into sponsoring cricket to the tune of £1 million over three years — big money in 1976. Ms Earl remembers how uncomfortable marketing directors were then with the idea of sponsorship, which caused shivers of fear in boardrooms. Once the deal was done, West shot in front of the BBC cameras at an Oval Test Match to announce the exclusive before Burrows had told his board.

Ms Earl recalls: “Everybody was happy — except the board. But it turned out to be brilliant. They were a smaller insurance company, not really known to the public and they stayed in for a long time. Cornhill reviewed it every three years but could not find anything to get that level of return. Research showed people thought they were huge, even when they were not.”

Even Strictly proves the power of a brand, a one-word title for many that represents hundreds of hours of television time and the gloss on several sporting careers, such as Gough and Ramprakash, who are probably now better known and to a wider public for dancing than cricket. Tufnell is but the latest to pull on his dancing shoes, although Ms Earl is not certain he can go the distance — even with that grin.

Yet Strictly’s ability to take people out of their pigeonhole is the same sort of lateral thinking that can make sponsorship effective and what fired Ms Earl when she set up her own company 25 years ago. It started as an all-woman business by accident, in a few rooms in a London house.

“I didn’t feel resistance as a woman in sport but I felt unique. I was quoted once as saying: ‘I didn’t employ men because you had to employ a woman to mop up after them.’ In those days, it was true because you would never see a man on a typewriter then.”

Now, with Karen Earl Ltd reinvented as Synergy and part of the Engine Group, a communications company, there are plenty of men happy to type on their laptops and mop up after themselves, working for a range of clients, whose names are attached to some of the world’s biggest sports events.

They have plenty to do, for sponsorship has stubbornly refused to bow to the worst of the recession, defying predictions of a collapse, as football’s Premier League showed last week, negotiating a £17 million increase, to more than £82 million, with Barclays for its three-year title sponsorship.

The devotion to building such a successful business has left precious little time for leisure. Ms Earl always wanted to try golf but never quite got there because she was so busy — even though one of her personal sporting heroes is Seve Ballesteros, the Spanish five-times major winner. “They tease me about him here,” she says. “He made me go weak at the knees because his whole persona and talent was fantastic.”

But Strictly is perfect, a Saturday evening wind-down when she can sit in her apartment overlooking the Thames, sip wine, text pals with her opinions on the contestants and dream of a Saturday night ringside seat. If only she could do something about Tuffers’ wayward feet — and his grin.

CV

Age: 57

Education: Hampden House, Great Missenden and Runton Hill, Cromer, Norfolk

Career highlights: starting Karen Earl Sponsorship in 1984; setting up Benson & Hedges Tennis Championships in 1976; first woman to run PR for the MCC; Karen Earl Sponsorship named agency of the year in 2005 by Marketing and in 2007 at the Sport Industry Awards; transforming Karen Earl Sponsorship into Synergy, with clients including Coca-Cola, RBS, British Airways, Diageo, Aviva, Betfair and Bupa; becoming chairman of the European Sponsorship Association

Other interests: Three-day eventing, sport, travel and musicals