Complex sentence: He transferred to Derby County for a fee of £7500 in September 1968, and by January 1969 had established himself in the Derby side that won promotion to the First Division at the end of his first season there.
Split into simpler sentences: He transferred to Derby County for a fee of £7500 in September 1968. By January 1969 he had established himself in the Derby side that won promotion to the First Division at the end of his first season there.