CHICAGO -- Zach Davies tugged at the brim of his hat for a moment as he closed in on the Cubs' dugout on Sunday night. He was walking off the field to a much-deserved standing ovation from the Wrigley Field faithful, following another stellar performance.

Since a brutal first month of the season, Davies has looked like a much different pitcher, doing his part to help the Cubs’ ascent in the National League Central. It was the same against the Cardinals, who were confounded by his low-octane arsenal in a 2-0 victory for the North Siders.

• Box score

The win completed a three-game sweep in a memorable series at the Friendly Confines, where fans filed in at full capacity for the first time in two years and shook the old ballpark all weekend. The rafters rattled again when closer Craig Kimbrel struck out the side in the ninth for the save.

"It's incredible," Davies said of the atmosphere. "Everybody's got life."

After Friday's raucous comeback win, manager David Ross said the fans played a role in the momentum shift. The energy only increased through Saturday and Sunday, when the Cubs played night games on the national stage. Davies said that feeling of a return to some normalcy has energized the team.

But while Davies' teammates thrived as the decibels climbed, the pitcher said he tried to mentally decrease the volume. For the right-hander, he needed the rowdiness to simmer to a white noise, helping his own return to normal continue on the mound.

"Personally, I try to block it out as much as I possibly can," Davies said. "You still hear it a little bit, but the way I pitch is less emotion, less adrenaline, more focus on execution and trying to get guys off-balance.

"So, the crowd, what it does for the team is a little bit different for me."

Davies found the right internal levels.

Davies gave the Cubs 6 2/3 shutout innings, which came after he baffled the Padres with six zeros on Tuesday in San Diego. Over his past nine turns in Chicago's rotation, the right-hander has fashioned a 1.86 ERA -- after laboring through April with a 9.47 ERA.

Against St. Louis, Davies mixed and matched -- leaning heavily on his signature combination of sinkers and changeups -- through 13 batters before finally allowing a hit. With one out in the fifth, Tyler O'Neill snapped that hitless run with a sharp single that went in and out of the glove of Patrick Wisdom. The third baseman promptly retrieved the ball and threw out O'Neill, whose thoughts of a double were wishful.

"The changeup seems to be devastating right now," Ross said. "He's got a nice feel for the rhythm of the game, the rhythm of the hitter, how to throttle them with that changeup and then even dropping in some breaking balls there."

During April, Davies allowed a .343 average and .486 slugging percentage against his changeup, per Statcast. Going into Sunday's outing, he had improved to an opposing .215 average and .323 SLG with the changeup since the calendar flipped to May. The Cardinals went 2-for-8 against the pitch.

"A few times, the changeup was up in the zone," Davies said. "But the way they swung at it, it was more disguised -- the way I saw it. So, it didn't have that much of an effect, being up in the zone with it."

Davies ended with six strikeouts, two walks and two hits allowed, while the Cubs' offense managed just enough support with a two-run second. As Ross noted, the changeup was again a great weapon for the pitcher, but he also held St. Louis to an 0-for-9 showing with his sinker.

"I talk a lot about fastball command," Ross said. "Right now, he's getting ahead with the fastball, knowing where that's going when he wants to throw the fastball. Early on [this season], I think there was a lot of pulled heaters to his glove side. It didn't have that real action coming back. Right now, he's got that action coming back."

Davies also credited the growing rapport he has with catcher Willson Contreras for his turnaround since April. The pitcher prides himself on reading swings and adjusting accordingly. Davies said Contreras has been integral in the same area in his recent outings.

"Willson sees a lot of it, too," he said. "Willson has been great behind the dish, getting pitches, getting called strikes. But at the same time, what I do best -- reading swings, reading approaches -- he's right there with me."

The Wrigley Field crowd was right there with them, too.

"The atmosphere was amazing," Ross said. "So, so thankful that fans are back in the ballpark. I think it just showed in our energy and us finding a way to win."