I've
heard this used to describe
baseball games where the
pitchers aren't very good and almost every
hitter gets one or two hits off of the pitcher. Usually a few of these are
home runs.
I've also heard this used to describe any
game where a
fight breaks out and lots of people are throwing
punches.
For example:
That Royals and Cubs game was a real slugfest. They combined for a total of 28 hits in the game.
The
hockey game last night turned into a
bench clearing slugfest when one guy ran into a
goalie.