my @matches = ($line =~ /$regexp/);

##</code><code>##

my $regexp = "\d+: (\d+):(\d+):(\d+),\d+,\d+,(\d+)\.+$";
my ($hr,$min,$sec,$match) = ($field =~ /$regexp/);
if ($match == '987') {
	... #do whatever you have to do with $hr,$min,$sec