It’s what you think it is.
A half-naked man (dis)graced the field at Miller Park on Thursday, causing a brief delay as security guards tackled him and prevented him from getting any closer to Giants shortstop Brandon Crawford.
Wearing a shirt, an undershirt (?) and socks, the man met his end at the hands of a pretty sound hit.
There are videos below that are somewhat SFW.
The San Francisco Chronicle had, er, a chronicle of the events.