Looks like there's at least a slight chance of rain leading up to tonight's first pitch at Camden Yards. When it rains, a baseball grounds crew is only as good as its tarp, a one-ton sheet of plastic that acts as the last line of defense to protect the infield.

But gnawing rats and normal wear and tear can leave holes in the cover, which means the Orioles crew must periodically get out a bucket of glue and hunks of plastic to patch openings large and small. Here's how they do it.