Complex sentence: Coldwell was an important part of the Worcestershire side that retained the Championship in 1965, but he was increasingly affected by hip and knee injuries and his wicket tally declined across the late 1960s, and he retired during the 1969 season, returning to Devon.
Split into simpler sentences: Coldwell was an important part of the Worcestershire side that retained the Championship in 1965. But he was increasingly affected by hip and knee injuries and his wicket tally declined across the later 1960s, and he retired during the 1969 season, returning to Devon.