NOTE: The original OP had
    DB<1> $line = "\"quoted text\" \cM\cJ"
(which does not match at all) in place of the current
    DB<1> $line = "\"quoted-text\" \cM\cJ"
(which matches as I would expect). Please be aware that silent updates like this can be very annoying. Please see How do I change/delete my post? for site etiquette and protocol regarding editing posts.

... the wrong result for array element 2.

I'm not sure what you mean by this: can you please clarify? Old and new strings match (update: and capture) as I expect. (Update: But I can only run Perl version 5.14.4 at most. (Further Update: I get the same results from my script running under 5.10.1, both Strawberry.)) 

use warnings;
use strict;

use Data::Dump qw(pp);

print "perl version $] \n\n";

for my $line (
  "\"quoted text\" \cM\cJ", "\"quoted_text\" \cM\cJ", "\"quoted-text\"
+ \cM\cJ"
  ) {

  print 'line: ', pp($line), "\n";

  my @ra;

  @ra = $line =~ m/^(\s*)((?'quote'"?)[^\s"]*\g{quote})\s+(\[[^\]]*\]|
+)\s*$/;
  print 'rx 1: ', pp(\@ra), "\n";

  @ra = $line =~ m/^(\s*)((?'quote'"?)[^\s"]*")\s+(\[[^\]]*\]|)\s*$/;
  print 'rx 2: ', pp(\@ra), "\n";

  @ra = $line =~ m/^(\s*)(("?)[^\s"]*")\s+(\[[^\]]*\]|)\s*$/;
  print 'rx 3: ', pp(\@ra), "\n";

  @ra = $line =~ m/^(\s*)("?[^\s"]*")\s+(\[[^\]]*\]|)\s*$/;
  print 'rx 4: ', pp(\@ra), "\n";

  }

[download]
Output: 
c:\@Work\Perl\monks\Ach>perl regex_problem_1.pl
perl version 5.014004

line: "\"quoted text\" \r\n"
rx 1: []
rx 2: []
rx 3: []
rx 4: []
line: "\"quoted_text\" \r\n"
rx 1: ["", "\"quoted_text\"", "\"", ""]
rx 2: ["", "\"quoted_text\"", "\"", ""]
rx 3: ["", "\"quoted_text\"", "\"", ""]
rx 4: ["", "\"quoted_text\"", ""]
line: "\"quoted-text\" \r\n"
rx 1: ["", "\"quoted-text\"", "\"", ""]
rx 2: ["", "\"quoted-text\"", "\"", ""]
rx 3: ["", "\"quoted-text\"", "\"", ""]
rx 4: ["", "\"quoted-text\"", ""]

[download]

Give a man a fish:  <%-{-{-{-<

In reply to Re: Captured single quote results in captured phantom quote by AnomalousMonk
in thread Captured single quote results in captured phantom quote by Ach

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