code: function round2Index(method, round) {
          if ('undefined' === typeof round) {
              round = this.node.game.getCurrentGameStage().round;
              if (round === 0) {
                  throw new Error('MatcherManager.' + method + ': game stage ' +
                                  'is 0.0.0, please specify a valid round.');
              }
          }
          if ('number' === typeof round) {
              round = this.matcher.normalizeRound(round);
          }
          return round;
      }
docs: ## Helper Methods. 
  ### round2Index
  
  Parses a round into corresponding index of matches
  
  Important! Matches are 0-based, but rounds are 1-based.
  `Matcher.normalizeRound` takes care of it.
  
  @param {number} round Optional. The round to parse to an index.
  Default: current game round.
  
  @return {number} The normalized round
  
  @see Matcher.normalizeRound
  @see Matcher.x
  @see Game.getCurrentGameStage