You could also literally count the number of matches and only start replacing from the second match onwards: 

use strict;
use warnings;

my $s="foofoo";
my $ctr = 0;

$s =~ s/(foo)/$ctr++?"bar":$1/ge;

print "$s\n";

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In reply to Re: Regex match and replace by hdb
in thread Regex match and replace by Anonymous Monk

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