"We have an interest in Diego Tristan," said Allardyce.
"He is a player with a very good track record who is available because of his situation at Deportivo.
"The difficulty for us is that a number of clubs may also be interested, who he could perceive to be bigger than we are or are offering more money, so we will see how we go on."
Meanwhile, Sam Allardyce has also told Portsmouth it will cost them £6 million to sign defender Tal Ben Haim.
The Bolton boss said: "We've had enquiries for Tal, but nobody has come near our valuation."