On a 2-0 fastball from Royals starter Sidney Ponson, Mauer turned his very first swing back in the Majors into an opposite-field home run.
The home run was just the start of a strong offensive night for the catcher as he went 2-for-3 with a double and three runs scored.
It's just one game, but the successful performance gave the Twins hope that one of their main offensive catalysts isn't about to miss a beat now that he's back.
"We all know what kind of hitter he is and what kind of swing he has," Gardenhire said. "He was swinging the bat good down [in Florida]. He probably got 40 or 50 at-bats. Some guys can do it [get their swing back] a little bit better than others. He's one of those guys.
"It was a different feel on the bench with him there. He brings that effect. We said he would and he did."
After missing the first 22 games of the season due to an inflamed right sacroiliac joint, Mauer, a St. Paul native, was greeted with quite the homecoming from the fans at the Metrodome.
The crowd of 24,727 gave Mauer a standing ovation as he stepped to the plate for the first time with two outs in the first inning. The catcher, eager to get his first at-bat out of the way, seemed appreciative if not a little uncomfortable with the ovation. But three pitches later, he gave reason for an even bigger roar when he hit the homer into the left-field seats.
For the normally stoic Mauer, the big smile on his face was hard to hide after he rounded the bases and returned to the dugout -- just in time to get some chiding from his teammates.
"I think there were at least a couple guys saying, 'Is it that easy?'" pitcher Kevin Slowey said. "It's not, but he makes it look very easy out there."
As for the homer, Mauer said he certainly didn't expect that type of result in his first at-bat.
"Maybe I let out a little frustration," Mauer said. "It was a rough offseason for me and an even worse spring. It's all worth it to be back up here with these guys. It's a lot of fun."
Mauer's next plate appearance came in the fourth with the Twins trailing, 2-1. This time he fell behind Ponson, 0-2, before the Royals pitcher, and Mauer's former Twins teammate, left a breaking pitch up that Mauer lined into the left-field corner for a double.
It was the first of six hits that Ponson would give up that inning as the Twins scored four runs to take a 5-2 lead.
But while Mauer was finding success at the plate, behind it the catcher was having more difficulty getting Slowey through some problems in his start. Right after his team had given the right-hander a lead, Slowey gave it away -- allowing three runs in the fifth as the Royals knotted the game at 5.
All of the problems came after Slowey had retired the side in each of the first two innings.
"I kind of painted myself into a corner," said Slowey, who gave up five runs on eight hits over five innings. "The first couple innings did go well, but I didn't show a lot of breaking balls, a lot of stuff in the dirt. I didn't earn a lot of bad swings late in the game. It was a case where I'm not thrilled with how I threw, but I'm thrilled we got a win."
It was Mauer again and the other half of the Twins' M&M duo who helped earn Slowey his fourth win of the season.
With one out in the bottom of the fifth, Mauer drew a walk from Ponson and Justin Morneau followed it up with his sixth home run of the season -- a 414-foot shot to right-center field -- which gave the Twins a 7-5 lead.
The Twins' bullpen held that lead as Matt Guerrier breezed through two scoreless innings, throwing just 12 pitches, and Jose Mijares struck out the side in the eighth for the second time in his last two appearances. Closer Joe Nathan came in for the ninth and recorded his fourth save of the season, securing the Twins' fifth win in their last seven contests.
The win also helped push the Twins over the .500 mark for the first time since the third game of the season, moving their record to 12-11. But that was not nearly as big of a lift for the club as seeing Mauer back in uniform once again, especially considering that he had no problems with his back during the contest and experienced only the normal soreness that comes from getting back into playing shape.
And of course, the fact that Mauer's swing is looking like it's in midseason form couldn't do anything but boost the club as well.
"I felt pretty good at the plate and like I was seeing the ball pretty good," Mauer said. "It still is going to take some time. Tonight I saw the ball well. Hopefully tomorrow I see the ball just as good."