Twins manager Ron Gardenhire benched third baseman Danny Valencia on Sunday.

Asked if it was a "Danny Day," meaning a chance for Valencia to get a breather, the manager said, "I call it a Gardy Day."

Gardenhire said this tongue-in-cheek, during his pregame media session, but insiders say the team's dissatisfaction with Valencia is growing.

From a distance, Valencia might seem low on a Twins' list of concerns, especially after they got swept at home by the White Sox, falling 12 games under .500 with Sunday's 7-0 loss.

But as the Twins contemplate how their roster should look for 2012 and beyond, not everyone views Valencia as the long-term answer at third base. In fact, some privately hope Joe Mauer adds third base to his repertoire, much as he has with first base, so he can play there on days he doesn't catch.

With 58 RBI, Valencia is two behind Michael Cuddyer for the team lead, but much of the frustration stems from his defense and what some perceive as a me-first attitude. In Saturday's loss, he made his team-leading 16th error, missing a throw from catcher Drew Butera on Juan Pierre's stolen base.

"Our biggest thing with Danny is separating the offense [from defense]," Gardenhire said. "Sometimes you can see his mind's on something other than defense. If your mind's wandering, and you're looking around and you're thinking about at-bats, you're going to miss plays. We've seen him wandering where we've had to yell at him to focus more than once, and you can't let that happen."

Gardenhire said it's not uncommon for younger players to focus too much on offense.

"He's worked really hard on ground balls," Gardenhire said. "He's taken them every day. He does all his work, so it's not like he's cheating himself. But you've got to focus, put as much out there when the game's going on defensively as you do offensively."

Valencia, who turns 27 next month, committed just six errors in 85 games last year as a rookie. He also showed better range. According to fangraphs.com, Valencia's ultimate zone rating was 5.9, meaning he saved the Twins 5.9 runs defensively compared to the average third baseman.

This year, his UZR is minus-3.0, meaning he's cost the team three runs on defense.

"I've just been inconsistent out there, really," Valencia said. "I make really good plays, and then I catch a ball, have all the time in the world and throw it over Mauer's head the other day. There's really no explanation other than, that just can't happen."

It looks worse when players aren't hitting. Valencia batted .311 last year and posted a .799 OPS. Some of that was luck. His batting average on balls in play was .345, and the correction has come this year; that number is .271.

Add it up, and Valencia is batting .244 with 12 homers and a .674 OPS. He also leads the team with 111 games played.

"If this is a bad year, I'm going to have a really bright future as far as I can see because I'm still producing, still driving in runs," said Valencia, who has batted .300 since the end of June, raising his average 26 points from .218. "It's a learning process, and there's still plenty of time. I mean, at the end of the year, if I'm still hitting .270, are we still going to talk about this?"

Even if Valencia improves the numbers, he'll have to improve perceptions. Gardenhire inserted him as a ninth-inning defensive replacement Sunday, with the Twins losing 7-0. That's not the type of assignment managers usually give to established players.

The Twins don't mind Valencia's confidence. They just don't want him to get too comfortable. At least not until he finishes his first full season in the majors.

Joe Christensen • jchristensen@startribune.com