Fabiano Caruana notched the result of his life at the Sinquefield Trophy in St Louis last year. Since then he has done nothing in particular and not done it very well, to adapt W.S. Gilbert’s lordly formula from Iolanthe. Now Caruana has reasserted himself at the elite tournament in Dortmund, where final scores (out of 7) were as follows: Caruana 5½, So and Nisipeanu 4, Kramnik 3½, Nepomniachtchi and Naiditsch 3, Hou Yifan and Meier 2½.
 
As can be seen, Caruana outclassed the field by a substantial margin, in spite of losing one game to Wesley So.
 
Nisipeanu-Caruana, Dortmund 2015 (see diagram 1)
Black’s plan of advancing the a-pawn is obvious. However, the brilliant tactic that makes it work is not. 27 … a5 28 Nd4 axb4 29 Nxc6 b3!! 30 Rxc7 Nd6 White resigns Despite the extra rook White has no way to prevent the b-pawn from promoting.
 
So-Kramnik, Dortmund 2015 (see diagram 2)
Wesley So handled this tricky endgame perfectly to keep the black queenside pawns under control. 67 Rf4 Kb3 68 Nxb4 Re7+ 69 Re4 Rg7 The point of White’s play is that 69 … Rxe4+ 70 Kxe4 Kxb4 loses to 71 Kd3 Kb3 72 g7 and White promotes with check. 70 Rg4 Re7+ 71 Kf3 Rg7 72 Nc6 Rg8 73 g7 c2 74 Nd4+ Kc4 75 Nxc2+ Kd5 76 Rg6 Black resigns
 
Kramnik-Caruana, Dortmund 2015 (see diagram 3)
Here Kramnik would be fine with the paradoxical plan of marching his king up the board, starting 28 Kd4. The king will actually be much safer after racing north-west into the black position. After 28 Kd4 Rd1+ 29 Kc5 the position is balanced. 28 Rd7 Rb1 29 Rb7 c5 30 Rb5 Rf1 31 Nd2 Now White becomes hopelessly uncoordinated. He had to play 31 Rxc5 Qg2 32 Qxh6 Qf2+ 33 Kd2 when 33 … Qxc5 34 Qg5+ is perpetual and 33 … Rd8+ is met by 34 Rd5. 31 … Rc1 32 Qb2 Rd1 33 Qc2 Rh1 34 Nf3 Qg2 35 Qc3 Rf1 36 Qf6 Rf2 37 Kd3 Rxe2 38 Ng5 Rd2+ White resigns