You're right; $2 is getting clobbered when your second regex succeeds. You need to save it away in another variable someplace before you do your next regex. A simple test:

my $string = "one two three four five";
my $tmp    = "this doesn't matter";

$string =~ /(\S+) (\S+) (\S+) (\S+) (\S+)/;   # $1 through $5 are set
print "\$3=$3\n";

$tmp =~ s/\S*$//;                             # random regex
print "\$3=$3\n";
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The output (with warnings):

$3=three
Use of uninitialized value in concatenation (.) or string at test line
+ 10.
$3=
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