The German master Adolf Anderssen was considered the best attacking player in the mid 19-century and his combinations were remarkable. His friendly game against Kieseritzky in London in 1851 was called the "immortal game." One year later in Berlin, he created the "evergreen game" against Jean Dufresne. Svidler might had the former game in mind when he referred to Anderssen. The white rook delivers the final blow on the same sqaure as Svidler did with his black rook.
20.Rxe7+!
Nxe7!?
[20...Kd8
21.Rxd7+!
Kc8
(21...Kxd7
22.Bf5+
Ke8
23.Bd7+
Kd8
24.Bxc6+
with mate; 21...Ke8
22.Re7+
Kd8
23.Be2+
Bd4
24.Bxf3
and white mates soon.) 22.Rd8+!
Kxd8
(22...Rxd8
23.gxf3
wins; or; 22...Nxd8
23.Qd7+!!
Kxd7
24.Bf5+
Kc6
25.Bd7#
) 23.Be2+
Nd4
24.Bxf3
Bxf3
25.g3
Bxd1
26.Qxd1
and white should win the endgame.]
21.Qxd7+!!
Kxd7
22.Bf5+
Ke8
23.Bd7+
Kf8
24.Bxe7#
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