Mauer had three hits, drove in two runs and was flawless in his first game at first base as the Twins beat the Chicago White Sox 6-2 on Thursday night.
"Teammates were supporting me, it was a lot of fun," Mauer said. "It was good to see the smiles and get a win. That's probably why I was most nervous because I wanted to make the plays for my teammates."
Mauer, the 2009 AL MVP, had started 714 games in the major leagues in the field, all at catcher. He last played first base in 2002 in Class A.
"It's pretty incredible," Twins starter Carl Pavano said. "I know Joe was probably a little nervous but none of us were. We know what kind of athlete he is."
In the bottom of the first, Mauer was immediately tested at his new position. He nabbed Omar Vizquel's hard liner to start an unassisted double play. Then he scooped a grounder hit by Adam Dunn and stepped on first, accounting for all three outs in the inning.
"I'm just glad it's over with," Mauer said. "I think that first inning was good for me personally to get a couple of balls hit at me. I had a lot of fun tonight."
Ben Revere also had three hits and two RBIs for the Twins, who beat Chicago for the eighth straight time.
Pavano (6-6) allowed six hits and two runs over seven innings for Minnesota, which has won 27 of 33 overall against its AL Central rivals. He walked two and struck out four.
"It always helps with that nice lead the guys gave me off the bat," Pavano said. "We put up some nice at-bats against a guy that's really been successful this year. I think we took advantage of some bad counts he got into."
Chicago right-hander Phil Humber (8-5) lasted 3 2/3 innings, allowing season-highs of 11 hits and six runs.
Tsuyoshi Nishioka had two hits and scored two runs for the Twins, who had 13 hits, including 12 singles.
"We were running around the bases pretty good, slapping the ball around," Twins manager Ron Gardenhire said. "Executed, got on second, got them over and got them in. A lot of things went our way early in the ballgame tonight against a very good pitcher."
Mark Teahen hit his third homer for Chicago, a two-run shot in the fifth.
"It was not a whole lot of fun out there," Humber said. "Even when I did execute my pitches it seemed like they were putting the barrel on the ball."
Minnesota has beaten Chicago all five times in their meetings this season and have won 13 of its last 15 games at U.S. Cellular Field. The White Sox have dropped four of five overall.
The Twins had been working out Mauer at first base in batting practice recently, hoping that an occasional respite from the rigors of catching will keep him fresh while keeping his bat in the lineup.
"It was exciting watching Joe over there at first base," Gardenhire said. "We never knew what would happen. They attacked him right away. He handled everything pretty good. He's an athlete."
Despite all the attention focused on Mauer's temporary position shift, the first base alternative is just that for Gardenhire, an occasional option to keep Mauer's bat in the lineup.
"We'll see what I feel like tomorrow," Mauer said. "The manager asked me to go over there and play. That's what I did tonight. I had fun doing it. But I'm a catcher. I think sometimes we lose track of that, but that's what I'm here to do."
One of baseball's biggest surprises this season, Humber had gone 6-1 with a 2.52 ERA over his last 10 starts, leading to cries that he should have made the AL All-Star team. He didn't show that form Thursday, as the Twins jumped on him with an aggressive small-ball attack from the outset.
Minnesota broke on top in first when Revere singled, stole second, went to third on a fly to right and scored on Mauer's single through the box.
The Twins tacked on two runs in second. Danny Valencia led off with a double, went to third on a groundout and scored on Nishioka's single up the middle. Nishioka then stole second and scored on Revere's single to center.
"They executed everything they had to execute early in the game," White Sox manager Ozzie Guillen said. "Everything. Get on base, steal, move the guy over. Score, steal, move the guy over, score."
The singles attack against Humber continued in fourth, knocking him out of the game.
With one out, Nishioka, Drew Butera and Revere all singled, scoring the first run. Alexi Casilla struck out, but Mauer singled to right, scoring Butera. Paul Konerko took the throw in from right and then flipped toward Gordon Beckham, who was backing up first base, trying to catch Mauer napping. Instead, the ball rolled behind Beckham, allowing Revere to score and putting the Twins up 6-0.
Michael Cuddyer followed by lining a shot off Humber, reaching on the 10th single among Minnesota's 11 hits to that point. He was the last batter Humber faced.
"(Humber has) been throwing the ball great," Mauer said. "I caught him a couple of years ago and he's really put it together. We were just trying to get pitches we could handle."
Rookie lefty Hector Santiago retired the first eight batters he faced and threw 4 1/3 scoreless innings.
Teahen got the White Sox on board in the fifth with his homer to the opposite field, cutting the Twins' lead to 6-2. Chicago could have gotten more if not for a couple of solid defensive plays by the Twins.
First, Mauer went to his knees to stop a grounder Vizquel, probably saving a run. Then Nishioka definitely saved a run, ending the inning with a diving snag of Konerko's smash into the hole and a throw to a stretching Mauer at first.
Before the game, it was announced that Konerko had won MLB's "final vote" and earned the last spot on the AL All-Star roster. Konerko received a loud ovation when he came to bat in the first inning. This will be his fifth All-Star appearance. ... Twins trainer Rick McWane said that an MRI on starter Scott Baker showed a mild flexor strain. As a precaution, Baker will skip his scheduled start on Sunday and will be re-evaluated after the All-Star break. He is undergoing treatment for the injury and isn't being allowed to throw. ... Santiago had the longest scoreless relief outing for the White Sox since Tony Pena threw six shutout innings against the Oakland Athletics on Sept. 20.