Back in 2009 a lot of the murals on the Reynolds Way wall were replaced. The originals had been subjects chosen by local young people in 2002, including a St George Flag, a Saky Tag, and a picture of Muhammed Ali. Ali was well remembered down that way because he used to visit a house in Saxton Road to see an old friend and supporter.
Perhaps there should be a road sign or something in his memory, not just a makeshift poster on the back of a telephone box.
(Thanks to Martin for the link in the comments. Here are pictures of Muhammed Ali in Abingdon from the BBC.)