Seems I forgot this one : Welling's line.

I was glancing through my collection of blogs I wrote for a year and a half now, and it seems I seldom wrote on the O'Kelly ( or Ziegler if you prefer ) defense.

Today I will cover Welling's line, occuring after 1.d4 d5 2.e4 dxe4 3.Nc3 Nf6 4.f3 exf3 5.Nxf3 c6 6.Bc4 Bf5 7.00 e6 8.Ne5 and now black captures the pawn on c2 : 8...Bxc2 (diagram)

Black gets a great game if wgite captures the bishop immediately, eg 9.Qxc2 Qxd4+ 10.Kh1 Qxe5 (=+). Fortunately, white has the great sacrifice 9.Nxf7, after which black has two options : 9...Bxd1 and 9...Kxf7.

Let's look first at 9...Bxd1 10.Nxd8 (diagram)

a/ 10...Kxd8 11.Rxd1
...a1/ 11...Nbd7 12.Bxe6 (+=)
...a2/ 11...Kc7 12.Bxe6 (+=)
...a3/ 11...Ke7 12.Re1 (+=)
...a4/ 11...Be7 12.Bxe6 (+=)
...a5/ 11...Bd6 12.Bxe6 (+=)
...a5/ 11...Bb4 12.Bxe6 (+=)

The alternative 9...Kxf7 seems better at first sight, but that assessment changes quickly after drilling down on 10.Qxc2 (diagram). ( Note that I also suggested 10.Bxe6+ Kxe6 11.Qxc2, but it seems black might escape after 11...Kd7 ).

After 10.Qxc2, black is forced to capture on d4, but this leads to disaster after the surprising 10...Qxd4+ 11.Be3!! (diagram).

White offers another piece, but this strategy wins in all lines :

b/ 11...Qxe3+ 12.Kh1
...b1/ 12...Bd6 13.Rae1
......b1a/ 13...Qh6 14.h3 (++)
......b1b/ 13...Qd4 14.Ne4 (+)
......b1c/ 13...Qc5 14.Ne4 (+)
...b2/ 12...Be7 13.Rae1 Qd4 14.Qe2 (+=)
...b3/ 12...Bb4 13.Rae1 Qd4 14.Qb3 (+)
...b3/ 12...Ke8 13.Rae1
......b4a/ 13...Qg5 14.Ne4 Nxe4 15.Qxe4 (++)
......b4b/ 13...Qh6 14.Qb3 (++)
......b4c/ 13...Qc5 14.Ne4 Nxe4 15.Qxe4 (++)
......b4d/ 13...Qb6 14.Ne4 (+=)
......b4d/ 13...Qd4 14.Rxe6+ (++)
...b4/ 12...Qg5 13.Ne4 (++)
...b5/ 12...Qh6 13.Qb3 (++)
...b5/ 12...Qb6 13.Qf5 (++)

c/ 11...Qxc4 12.Rf4
...c1/ 12...Qxf4 13.Bxf4
......c1a/ 13...Bc5 14.Kh1 (+=)
......c1b/ 13...Nbd7 14.Be3 (+=)
......c1c/ 13...Be7 14.Rf1 (+)
...c2/ 12...Qa6 13.Ra4

......c2a/ 13...Qxa4 14.Qxa4 (+)

......c2b/ 13...Be7 14.Rxa6 Nxa6 15.Rf1 (+=)
......c2c/ 13...h6 14.Rxa6 Nxa6 15.Rf1 (+=)



Hope you appreciate this fantastic line - I sure do !