Ireland's rugby heroes will earn only a fraction of the endorsements and sponsorships secured by Padraig Harrington after his victories at two of golf's major tournaments last year.

On the back of last week's historic grand slam, experts estimate that Brian O'Driscoll, Ronan O'Gara and the rest of the victorious team stand to earn anywhere from €100,000 to €300,000 each – a tidy sum, but minuscule compared to the tens of millions of dollars Harrington can look forward to earning over the coming years.

Harrington's biggest deals include a reported €7.8m renewal deal with his clubmaker Wilson and a three-year, €12m deal simply to put the logo of American business consultancy FTI on his visor.

In total, Harrington has 10 personal endorsement deals.

The main barrier to these types of figures being earned by the rugby players is the recession, said Johnny O'Shea of Platinum One, the sports marketing company which represents Luke Fitzgerald, Gordon Darcy, Jamie Heaslip, Denis Hickie and Shane Horgan.

"It's going to be very apparent over the next few months that the brands will seek to capitalise on [the Grand Slam victory, but] the players' expectations will have to be tempered because of the current economic climate."

There will be opportunities, however. "With the current Irish squad, I would be surprised if the brands, particularly Irish brands, didn't see the platform that these guys can give them", said O'Shea, "particularly when the soccer stars, for example, are not based in Ireland.

"Rugby has gotten bigger; it is a more global sport now. The match on Saturday had 1.2 million viewers on RTÉ. These guys are now national properties and successful properties."

Endorsements and sponsorships are not the only areas of financial promise. Book deals, particularly now that they can document one of Ireland's greatest ever sporting achievements, could be a money-spinner.

"There are at least four members of the team planning books for this year," said John O'Connor, managing director of Blackwater Press.

"Most of them at one stage would have been approached and they would have said, 'Let's get the timing right.' You don't get timing any better than this."

And as with everything, the pay cheques involved will vary.

"If you are going to do a book on a Grand Slam player, you would have to have 40 to 50 grand as an advance for a high-profile player and about €20,000 for a low-profile player.

"O'Driscoll could start from scratch [on a new book] and he would make at least €100,000."

Publishing experts also believe that O'Gara's book – which did very well on its recent release, selling about 20,000 copies – could get another boost from last week's win, although simply adding another chapter would not be as easy as people think.

Talking to a room full of businessmen about the motivation and dedication it takes to succeed would also prove lucrative.

"They are definitely more in demand, sports speakers always are, because of the motivational qualities," explained Susan Thornber, founder of the Speaker Solutions agency.

"Now because of the success of the team, the rugby players will be in big demand. You can draw a lot of parallels between business and sport, and at the moment we need some good news.

"Who are better than the Grand Slam winners to address these themes? They can speak about the difficulties facing business teams and those facing sporting teams and how they can use the same kind of strategies to succeed."