But ask him about the knee and the answer is clear: It's nothing that will keep Mauer off the field.
"It doesn't really matter right now," Mauer said when asked how his knee is feeling. "It is what it is. I'm out there and it was good to get into a game the other day and catch the whole game. I was able to get through it and so it was good. This time of the year, everybody is kind of grinding it out and I'm not any different."
Injuries took a toll on Mauer in the first half of the 2010 season. He batted .293 before the All-Star break, which would be considered a solid start for most hitters, but they were pedestrian numbers by the high standards that the 27-year-old catcher has set for himself. And there were questions as to what was wrong with the reigning AL MVP.
Since returning from the break, Mauer has turned things around offensively, and perhaps it's no surprise that the Twins' second-half run coincided with his hot streak.
In 60 second-half games, Mauer batted .373 with a .447 on-base percentage. It raised his season average to .327, which ranked him third in the AL. And with Mauer's surge helping to bolster Minnesota, the club captured its sixth AL Central title in the last nine years a full 12 days before the end of the regular season.
Not exactly what you would call a down season, right?
"We've been playing well all year, and it's been a different guy every part of the way," Mauer said as he sat by his locker at Target Field on Sunday morning. "For us to be in the position we're in right now heading into the postseason is really what matters the most. Obviously, I'm happy to contribute to that. As far as personal things go, I guess it's good. I had a rough first half. I was beat up, and when you have an injury in baseball and it starts early, you're dealing with it the whole way through. How much I've been out there and been able to stay on the field means more to me than anything."
The Twins certainly aren't surprised to see Mauer battle through injuries like he's done this season. Last postseason, Mauer was bothered by a sore hip flexor, which he suffered during the club's 12-inning win over the Tigers in Game 163, but he still kept playing in all three games against the Yankees in the ALDS.
So while his current sore knee might keep Mauer from going full speed, it won't keep him from trying to help his team accomplish its goal of making a run deep into the postseason.
"I would imagine you might notice it if he hits a ball in the gap, how he's running out to second base," Twins manager Ron Gardenhire said of the knee. "You might see something like that, but he sure hasn't shown it on the field. He's run through first base just fine. He's not limping around. He said once everything gets loose, he's a lot better. I think that's what we're all waiting to see, if it's a noticeable thing."
Perhaps the only people that really have an idea of what Mauer has battled through this season are his coaches, teammates and family. The catcher doesn't like to openly discuss his injuries -- whether it was a sore shoulder that bothered him heading into the All-Star break or the bruised heel that he suffered in early May.
"He's been dealing with some nagging injuries," said Twins veteran slugger Jim Thome. "It doesn't get talked about a whole lot, but we as teammates see it. You respect a guy that goes out there at his position and does what he does."
When the Twins needed a lift in the second half after losing All-Star first baseman Justin Morneau to a concussion on July 7, Mauer was one of the players who elevated his game.
"Maybe I was just feeling a little better physically," Mauer said. "I don't know about any more to that. I think everybody knows what Justin brings to our team. I wasn't trying any harder to do anything differently. I just felt a little bit better physically."
His teammates, though, have other explanations.
"Let's face it -- he's in the top five players in the game," said Thome. "Guys like that always rise to the top. That's the tough part of the game. There are going to be times where you don't succeed. And people are going to go, 'What's wrong? What's happened here?' I will say this: All the good players I've ever played with, they always come back and they don't panic. That was his case."
The St. Paul native and hometown star has risen to become one of the most recognizable players in the game. After his standout 2009 season, which earned Mauer his first AL MVP Award, his presence on the national media scene increased. He was featured in an episode of "Homecoming" on ESPN with host Rick Reilly, and he earned a cover on ESPN the Magazine with the distinction of "America's Fan-Friendliest Athlete."
Then came the eight-year, $184 million contract extension that Mauer signed with the Twins in Spring Training, ensuring he will remain in Minnesota through at least the 2018 season.
But while he's become the face of the franchise, and soon to be top-paid star, it doesn't mean that all of it has changed Mauer's personality or how he chooses to be a leader. The soft-spoken catcher doesn't attract attention in the clubhouse by being vocal. He instead makes his presence felt on the field.
"It's my personality," Mauer said. "I'll say something if it needs to be said. But I think my way of doing things is by working hard and leading by example. I think that can be just as effective."
Mauer's focus has always been about winning and getting to the postseason. He'd rather focus on team goals instead of talking about himself. But that doesn't mean that others can't focus on Mauer's accomplishments even in years where he's had to battle through various ailments and a slow start in the team's new ballpark.
There has been a lot of discussion as to who has been the Twins' MVP of the 2010 season. In a year where so many different hitters contributed, it can be tough to narrow down the selection to just one.
Gardenhire certainly seemed to be stumbled by the task recently when asked if he could narrow it down. But perhaps it's no surprise that when everything came down to it -- Mauer's name couldn't help but once again rise to the top.
"To say one guy over the long haul's been your overall MVP," Gardenhire said, as he thought about the question, "Joe's been really good all year for me."