Johnson heaped particular praise on midfielder James Wesolowski, who scored his first goal since December 2011.
"There were a lot of really good performances out there," he said after the Latics scored twice in the opening 10 minutes. "In the first half we showed really good quality and in the second it was really good character.
"For these young players it will give them a massive boost with the victory and clean sheet and having dug in with each other and that's important.
"They had a couple of chances when they threw caution to the wind but the back four looked quite comfortable.
"We knew we had to go for it early and our movement was really sharp early on."
He added: "I've been waiting for Wesolowski to score, he caught his strike well and I'm pleased for him because we've been ribbing the two central midfielders about not getting any goals yet."
- Sports & Recreation
- James Wesolowski