$s = "Test-01-xxx";
if ($s =~ /-(\d\d)-/g) {
  print "Pos: $pos - ", pos( $s )-3, "\n";
}

##</code><code>##

$s = "Test-01-xxx";
if ($s =~ /(.*?)-(\d\d)-(.*)/g) {
  print "The string was split into :\n"
  print "Left part : $1\n";
  print "Number part : $2\n";
  print "Right part : $3\n";
}

##</code><code>##

$s = "Test-01-xxx";
# Method 1, possibly slow
if ($s =~ /-(\d\d)-/g) {
  print "Pos: $pos - ", pos( $s )- length( $& ), "\n";
}

# Method 2, possibly slow
if ($s =~ /(-(\d\d)-)/g) {
  print "Pos: $pos - ", pos( $s )- length( $1 ), "\n";
}