"I am very proud of my players because they all worked their socks off," Johnson said after the goalless draw against the struggling Swans.
"I am very happy with a point and we could have snatched the victory right at the end.
"It is a squad game now and we have had to make full use of all our players as we have had several going down with a virus.
"Nicky Maynard had to be taken out of the starting line-up after reporting in unwell this morning."