Seems like reverse split reverse reverse is working a bit too hard.

my  $s = 'foo.bar.foobar';
my ($var1, $var2) = $s =~ m[(^.*)\.(.*?$)];
print $var1, $var2;

foo.bar foobar
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Note: The greedy .* in the first capture and the non-greedy .*? in the second.