Achterberg first signed for Tranmere Rovers in 1998, after a successful trial as a replacement for the Everton bound Steve Simonsen. He was immediately selected for the first team due to an injury to Danny Coyne, making his debut against Swindon Town on 25 September 1998. Achterberg then secured his place as Rovers' first choice goalkeeper after Coyne was transferred to Grimsby Townin 1999. Achterberg became part of the giant-killing cup teams that defeated such opponents as Everton, Southampton and other big teams. However after refusing to sign a new contract he was dropped by John Aldridge for the 2000 Football League Cup Final and replaced by Joe Murphy. Achterberg's proficiency in goal was exemplified by the 20 clean sheets he kept during the 2003–04 season under the stewardship of Brian Little. One of his more memorable performances was against Millwall in an FA Cupquarter final at The New Den which was televised on BBC 1. The game finished goalless, but was largely dominated by Millwall and John managed to save a penalty kick from Kevin Muscat, despite having to play through injury. Achterberg's 2005–06 season was less successful. After spending most of the season sidelined with injuries, he was replaced by Steve Wilson and Dino Seremet, who was on loan from Luton Town. Achterberg's chances of re-establishing himself as Tranmere's first choice goalkeeper in 2006–07 were hampered by the signing and good form of veteran journeyman Gavin Ward. Later in the season, an injury to Ward gave Achterberg a chance, but a re-occurrence of his own injury problems saw him sit out the closing months of the season. Achterberg's contract expired in May 2007 and he was released by Tranmere on 25 May. This resulted in uproar from many Tranmere fans, who believed that Achterberg deserved a testimonial match, despite him falling just short of the ten years' service usually required to earn a testimonial at a club. On 31 May, however, he was given a two-year coaching and player contract with Tranmere. Achterberg made his 300th Rovers appearance in the opening day game of the 2008–09 season against Swindon Town. Achterberg had his testimonial game in 2009 for Tranmere against an Everton XI.
Coaching career
After retiring from playing/coaching in 2009 with Tranmere Rovers, Achterberg joined Liverpool FC in June 2009 as a goalkeeping coach of the reserve and academy goalkeepers before being promoted to first-team goalkeeping coach in summer 2011.
