THE greatest in Chesterfield's long line of fine goalkeepers, Gordon Banks, ended his career with a winner's medal in the World Cup but not the FA Cup. The latest, Billy Mercer, feels embarrassed to be mentioned in the same breath, yet he could finish the season with the prize that eluded a legend. Mercer's trophy cabinet offers a true measure of Chesterfield's achievement in reaching the FA Cup semi-final, as well as the stakes for which the Second Division club are playing against Middlesbrough after their pulsating 3-3 extra-time draw. The solitary item on display was awarded for being an unused substitute in a glorified friendly called the Steel City Challenge. It is a loser's medal. Not that the 27-year-old Merseysider is acquainted solely with the unglamorous end of the spectrum. Having started late as a keeper at the age of 14 - 'No one else would go in goal at school,' he explains - Mercer recovered from the blow of being released from Everton's YTS programme to earn a contract across the city with Liverpool. Suddenly the self-confessed Kopite and trainee metal worker was working daily in training with Messrs Dalglish, Rush and Hansen. When Bruce Grobbelaar was injured and Mike Hooper took over he played 30 reserve games, while a loan to Rotherham brought League experience at 19. 'I was assured there was no way they'd let me go,' Mercer recalls, 'but when I came back Kenny Dalglish told me the clubs had agreed a fee. I was struggling to hold back the tears in his office, though with hindsight my career would probably have stalled if I'd stayed.' After six years at Rotherham a knee injury had cost Mercer his place when Dave Bassett rang asking him to join Sheffield United's tour of Australia. 'I thought it was the Rotherham lads pulling my leg. I was going 'Yeah, sure', but it was for real and I signed when we got back. 'The trouble was that I couldn't displace Alan Kelly, who's easily the best keeper I've worked with, and in my last three months there I went on loan to Nottingham Forest.' An eight-game stint as cover for Mark Crossley culminated in a visit to Wimbledon. 'It looked as if Frank Clark was going to put me on when Mark got a whack on the head, but it never happened.' So to Chesterfield, which is to goalkeepers what Newcastle is to centre-forwards. 'I'm not a flash 'keeper,' says Mercer. 'You've got to remember I worked with Alan [Kelly], who's the complete opposite to Bruce [Grobbelaar]. He's a textbook keeper and that's how I'd like to be. 'I've got great respect for Bruce. It takes a lot to perform consistently well at the highest level, where every error is magnified. The most important thing about goalkeeping is to forget your mistakes, which the top guys are never allowed to.' Mercer, who has kept 20 clean sheets this season, acknowledges that Sunday was more than 'just a game'. Old Trafford is one of a handful of grounds he had never visited, but there was one familiar face among Middlesbrough's exotic talents. Craig Hignett was a colleague in Liverpool's second string; their families have even holidayed together. Thinking about the replay, Mercer said: 'We know Juninho and Ravanelli are world-class attackers, but they've also got weaknesses we can exploit.'