Allardyce acknowledged the efforts of the club's co-chairmen David Sullivan and David Gold in signing the former England Under-21 international while the club were in the Championship.
"No one should underestimate Nolan," he told the London Evening Standard. "Look at his CV. Premier League, Premier League, Premier League - 10 goals, nine goals, 11 goals, nine goals etc. "I hope they (other clubs) underestimate him for the rest of the season and he will end up the joint top scorer like at Newcastle.
"He was great value for money in the Premier League but very expensive in the Championship - so give credit to David Sullivan and David Gold for spending that money on that sort of player."