Newcastle's placing, which closes today, aims to raise pounds 47.7m, valuing the Premier League club at between pounds 172m and pounds 193m. The offer to retail investors, aimed mainly at fans, ended yesterday.
But leading fund managers, worried about falling equity prices, were last night deciding whether to subscribe or not. "We don't have a view on it yet," said a spokeswoman for one financial institution. "Football clubs are difficult to value."
Football analysts said Newcastle's triumvirate of advisers - NatWest, Deutsche Morgan Grenfell and Salomon Brothers - would do everything in their power to avoid an embarrassing flop.
"The float will get away but there are definitely questions that have not been answered," said Guy Batram of Greig Middleton. "I can understand why people are uncomfortable with the issue."
Proceeds from the float will be used to pay off pounds 21m of debt. But concerns centre on how the club will fund plans to abandon its St James' Park home for a new pounds 90m stadium, replace stars such as David Ginola and Peter Beardsley, and develop a neglected youth policy without asking shareholders for more money.
The continued role of Sir John Hall in the running of the club has also raised eyebrows. Sir John, whose Cameron Hall property company will remain the majority shareholder after flotation, is stepping down from the main board but will remain chairman of the football club.
Despite the shaky state of stock markets, a spokeswoman for NatWest, brokers to the issue, insisted the flotation was going well. "The retail offer is going to be hugely oversubscribed," she said.
As Newcastle put the finishing touches to its flotation plans Tottenham Hotspur announced a rise in operating profits before transfer fees of pounds 7.1m (pounds 6.3m) in the six months to January.