HashMap<Integer, String> points = new HashMap<>();

        points.put(551, "Player1");
        points.put(554, "Player2");

        int higher = Integer.MIN_VALUE;
        String winner = null;

        if (higher == Integer.MIN_VALUE){
            higher = Collections.max(points.keySet());
            winner = points.get(higher);
            points.remove(winner);
        }

        System.out.println("Winner is " + winner);


Napsalo to vždycky správně...
Ale teĎ, když to mám naopak, tak nevím jak.