The Joe Mauer situation went from not scary at all, when he was initially day-to-day, to moderately scary, when he was placed on the disabled list with inexplicable bilateral leg weakness that was also affecting his hip and shoulders. But Mauer went to the hospital on Thursday night with flu-like symptoms, and the organization believes that virus may be responsible for what's going on with its prize backstop:

Twins now think viral infection Mauer was diagnosed w/ at hospital last night contributing heavily to his soreness and weakness Gardy said.
...
w/ viral infection diagnosed for Mauer, Gardy said he's much less concerned and more optimistic Mauer's DL stint will be brief

Obviously, we'll see. The Twins think Mauer is weak because of this virus, but until someone's able to confirm, he won't be entirely out of the woods. But the Twins are optimistic, and if Mauer is simply having trouble because he's been bogged down by an infection, it stands to reason he should be able to make a full and fairly fast recovery.

We can all cross our fingers. Love the Twins, hate the Twins, or think the Twins are okay, we can all agree that baseball is more fun when Joe Mauer's on the field, so hopefully this really is just about a bug.