Beside that is what appears to be the English flag, a red cross sitting over a white background, however, the fact that the ...

but mistakenly got the colours of the St George’s flag wrong. Nike revealed it had altered the cross using purple and blue horizontal stripes in what it called a “playful update” to the ...

This is also why St George’s cross is on the English flag: St George was traditionally depicted carrying or wearing a red cross on white background, and King Richard adopted it in his honour.