Black to move
Black played 34...Qd8 and twenty moves later the game ended as a draw. Chess teachers can find several positions in the last twenty moves worth putting in front of beginning and intermediate students with a question: should Black exchange bishops?
For example, After 47.Bd4.
Black to move
The average reader of Chess Informant does not need a prompt to recognize that 47...Bxd4 offers Black a hopelessly lost pawn ending.* However, this position should prove instructive when I put it in front of youth players who are struggling to rise to the level of solid C and D Class players.
Back to the first diagram, Rafael Leitao, who annotated the game for Informant noted the pitfall that he avoided. 34...Kf7? 35.Bxe7 Kxe7 36.Rc8 Qa5 37.d8Q+ Qxd8 38.Rxd8 Kxd8 39.Kf1.
Black to move
White would have had an elementary win in this pawn ending. Even so, my students may need to play this position out a few moves in order to understand how White wins.
After White's queen sacrifice, Black had to examine the bishop and pawn ending as well as a couple of possible pawn endings. Kf7 would be played, but the move order was critical. Black chose the correct transition to an ending with the bishops on the board.
* Edit 16 October: My superficial analysis led to gross error. The position that would have resulted had Black opted to exchange bishops on move 47 is not "hopelessly lost" for Black. See "Superficial Analysis".