Connections of Archipenko are under no illusions about the task their horse faces in the Group One Coral-Eclipse Stakes at Sandown on Saturday.The widely-travelled five-year-old took the Summer Mile at Ascot last season and did not get the clearest of passages in his latest outing, when trying to retain his QEII Cup title in Hong Kong during April.He ended up finishing a close sixth behind the Luca Cumani-trained Presvis.Juan Nel, who is overseeing the Newmarket arm of South African trainer Mike De Kock's operation, said: "He's doing well and his preparation so far has been as much as we could ask of him."He's ready to take his chance, but it's quite a strong field with the likes of Conduit and Sea The Stars - it's probably his toughest challenge to date."Nel expects in-form jockey Kevin Shea to be on board at the weekend.