Career
Donaldson began his career with Arsenal F.C. but never broke into the first team In June 1973, he transferred to Millwall F.C. for ₤5,000. He where he went on to play 216 league games over six and a half seasons for Millwall.
In summer of 1979, he went on loan to the Los Angeles Skyhawks of the American Soccer League.
On February 5, 1980, Millwall sold Donaldson"s contract to Cambridge United for ₤50,000. He played for Cambridge until 1984 and is listed among the 101 best players for the club