Ask what Black attacks and how his pieces bear on White’s king. His queen attacks White’s rook, which is protected by White’s queen. Does Black have a mate threat? He does, as is obvious if you remember not to overlook your pawns: Black’s h4 pawn attacks g3, and so does his queen; so Black almost can mate with Qg3. The only obstacle is the defense of g3 provided by White’s queen from c7. Since the queen prevents mate, attack it. The tool Black has available for the purpose is his rook. It can attack the queen two ways: Rc6 or Rf7. Rc6 loses the rook to RxR without budging the queen, but Rf7 requires the queen to move. As we know, when the queen is attacked in these circumstances it usually tries to just move to another square where it will be safe and still able to defend the mating square. Here that would mean a move for White like Qd6 or Qb8. But this time the queen has something else to worry about: it also is guarding the rook on c3. So when White plays Qd6, as he must to prevent mate, he loses his rook to QxR.

All this is well and good, but there is one more thing for Black to consider: as often is the case, White has the option of responding to Black’s threat with a counterthreat; thus when Black plays 1 …Rf7, White can try 2. Rc1, meeting the attack against his own queen with an attack against Black’s queen. The mistake for Black then is to assume play would go 2. …RxQ, 3. RxQ. Instead, Black should imagine the board after 2. Rc1 and ask what checks he would have. There would be a new possibility in 2. …Rxf3+. Since it’s a check, White would have no time to play RxQ. He would have to move his king to h2 or g2. Either way Black replies 3. …Qf2+, and the net grows tight; indeed, the rest is forced: 4. Kh1, Rh3+; 5. Qh2 (a formality), RxQ#. So the White counterattack 2. Rc1 is not something Black has to worry about.

So now back to a lesson of the main line of analysis: here is another way in which attacking a queen may be fruitful; if it protects pieces or other points as well as a mating square, then if it moves it may leave its protectorate exposed. In a word, the queen in this case is overworked, and this time Black takes advantage not by taking one of the queen’s protectorates but by attacking the queen directly. As we see here and elsewhere, a threat of this sort against an overworked piece has an unusually high likelihood of creating real trouble for your opponent. The piece may be able to move and still protect one of the points it is supposed to defend, but probably not both of them.