Replace With Alphabet Position

My:
object Kata {
  def alphabetPosition(text: String): String = {
    text.toLowerCase.replaceAll("[^a-z]", "").toList.map(x=>x.toInt-96).mkString(" ")
  }
}

Other:
object Kata {
  def alphabetPosition(text: String): String =
    text.filter(_.isLetter).map(_.toLower - 'a' + 1).mkString(" ")
}