It was Johnson's eighth NHL shutout, first since Nov. 30, 2016, for the Calgary Flames against the Toronto Maple Leafs.
"I don't really think about being locked in or on," Johnson said. "… I just try to feel the same way or not feel at all. You just go out there. You work hard. You're focused in the moment. What happens at the end of the day is the result that you get from your preparation. I felt I've been ready to go here and felt good with my preparation throughout the game. I'm just happy with getting the two points."
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In his past two starts, Johnson has allowed one goal on 72 shots, made 58 straight saves and has a 0.50 goals-against average and .986 save percentage.
"Chad was good; you're not going to have a game where you don't give up scoring chances, especially against a team like that," St. Louis coach Mike Yeo said. "You're going to give up some stuff, and I thought he was strong. I thought they slung a lot of pucks at the net and I thought he did a good job of controlling rebounds, steering them away."