There's no shortage of macho trash talk while playing blitz chess for money.
Whether that qualifies as a "combat sport" is another question entirely.
Chess as a combat sport!
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Josh Waitzkin on chess and martial arts (tai chi chuan, Brazilian jiu-jitsu):
http://www.onthemat.com/node/10011
http://www.youtube.com/watch?v=gTZS3SqpT-o&t=7m53s
Chess may have originally been invented as war simulation -- what do you think? But that may be off the topic because war involves lots of military and hardware, and we are talking here about chess as a combat sport. Sport and war, of course, are also vastly different!!