Complex sentence: At the end of the first season at Holt, Weller left to take over as manager of Wimborne Town, asking Pike to follow him, as his assistant, an offer which he declined, deciding to stay at Holt for the time being.
Split into simpler sentences: At the end of the first season at Holt, Weller left to take over as manager of Wimborne Town, asking Pike to follow him as his assistant. Pike declined the offer, deciding to stay at Holt for the time being.