Williams had long been a doubt for the double-header due to his ankle ligament injury and Swansea manager Michael Laudrup had made it clear the defender needed a rest.
But, with his squad so severely hit by withdrawals, Coleman would have wanted to field the 29-year-old if possible.
However, the result of a scan on the problem has seen him ruled out, and a Football Association of Wales (FAW) spokesman confirmed to Press Association Sport that Williams would return to his club.
It means Coleman is now without 10 of the 23-man squad he named last week as he prepares for two games which could decide his future.
Source: PA
Source: PA