Ashcroft made it through the youth ranks at Preston North End, coached by Walter Joyce. He turned professional at the Fourth Division club under John McGrath. Preston won promotion in 1986–87 after finishing as the division's runners-up. After retaining their Third Division status in 1987–88, the "Lilywhites" qualified for the play-offs in 1988–89, but lost out to Port Vale at the semi-final stage. Following this disappointment they dropped down to just two places outside the relegation zone in 1989–90. Preston finished 17th in 1990–91 and 1991–92 under Les Chapman, before suffering relegation in 1992–93 under the management of John Beck. He later admitted that "I had to get away when John Beck was manager".