Lawn Tennis Association chief executive Roger Draper has refused to predict how many British players will be ranked in the world top 100 in five years.
Although there are three British women ranked in the top 100, Andy Murray is the only Briton in the men’s top 100.
“We’re not making predictions. We don’t want to heap pressure on [youngsters’] shoulders,” Draper told BBC Sport.
But he said efforts to develop talent, given LTA investment of over £250m, were “over the years, not acceptable”.
Draper believes the recent success of George Morgan in junior events, as well as Heather Watson and Laura Robson who have also broken through on the senior tour, promises better times ahead for Britain’s tennis fans.
But he believes it will take another five years to rectify the problems facing British tennis.