He has since spoken of a desire to take the reins on a full-time basis and Nicol - who won 23 caps for Scotland - believes the Australian and forwards coach Dean Ryan are the perfect fit to take the country forward.
"I think Scott Johnson has proved that he has the tactical nous," said Nicol.
"He and [forwards coach] Dean Ryan have done everything they were asked so I would like to see him get the job.
"I think having won two games in the last three Championships surely we take two wins in this Championship as real progress
"The pair of them worked very well together. They have created an environment that the players like, it's a very happy camp.
"I think they have laid the foundations for real progress. It would be a bit ludicrous to take away that foundation and start again.
"He has brought a smile back to Scottish rugby, there is no doubt.
"The atmosphere at Murrayfield has been cracking in the three home games.
"If he is the right man, let's make that decision quickly and put it to bed."