void makeLink(Match match) {
        match.prevHTM = match.prevATM = null;
        if (prevMatch.containsKey(match.homeTeam)) {
            match.prevHTM = prevMatch.get(match.homeTeam);
        }
        if (prevMatch.containsKey(match.awayTeam)) {
            match.prevATM = prevMatch.get(match.awayTeam);
        }
        prevMatch.put(match.homeTeam, match);
        prevMatch.put(match.awayTeam, match);
    }