This is in response to the challenge at Tic Tac Toe by Jeff Connely. This weighs in at 202 characters. I like the chop part myself. :) 
$Z='ox'x5;$_="1 2 3\n4 5 6\n7 8 9 ";{$C=chop$Z;print 
"\n$_=>$C";{<>=~/^([\d])$/ && s/$1/$C/m or redo;}(
m/(^($C.){3})|(($C.{5}){2}$C)|($C.{7}$C.{7}$C)|(^.(...$C){3})/sm 
or ++$T>8) or redo;}s/\d/-/g;print

[download]

Update: My original character count was off a bit. I think 202 is correct though.

In reply to Tic Tac Chop by turnstep

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