The last straw

In our never ending story on Euwe's refutation of our beloved gambit occuring after 1.d4 d5 2.e4 dxe4 3.Nc3 Nf6 4.f3 exf3 5.Nxf3 e6 6.Bg5 c5!, I am presenting today white's last option.

I already discussed 7.Bxf6 Qxf6 8.Bb5+ and 7.Bxf6 Qxf6 8.d5. Today, I will be covering the simple 7.d5 (diagram).

a/ 7...Be7 8.Bb5+
...a1/ 8...Bd7 9.dxe6 (+=)
...a2/ 8...Nbd7 9.d6 Bf8 10.00 (+=)
...a3/ 8...Nfd7 9.dxe6 fxe6 10.Qe2 (+)
...a4/ 8...Kf7 9.00 (=)

b/ 7...Bd6 8.Bb5+ (+=)

c/ 7...exd5 8.Bb5+
...c1/ 8...Nc6 9.Bxf6 (+=)
...c2/ 8...Nbd7 9.Nxd5 (+)
...c3/ 8...Bd7 9.Nxd5 (+=)

d/ 7...h6 8.Bxf6 (+=)

e/ 7...a6 8.dxe6 (diagram)

...e1/ 8...Qxd1+ 9.Rxd1
......e1a/ 9...Bxe6 10.Bxf6 gxf6 11.Nd5 Bxd5 12.Rxd5 (=)

......e1b/ 9...fxe6 10.Bd3 (=)
...e2/ 8...Bxe6 9.Qxd8+ Kxd8 10.000 (=)

...e2/ 8...fxe6 9.Qxd8+ Kxd8 10.000 (+=)


So it seems white enjoys a small advantage in the majority of lines, except when black chooses the single right answer, the surprising 7...a6.

We have now come to the end of our journey in Euwe's refutation of the Blackmar Diemer. In "A bit of a setback", I discovered the problem.

Blogs "An update of the refutation of the refutation !?" and "An update on the refutation of the refutation (part 2)" discussed 6...c5 7.Bxf6 Qxf6 8.Bb5+ Bd7.

"More complicated Euwe defenses" analysed 6...c5 7.Bxf6 Qxf6 8.Bb5+ Nd7.

6...c5 7.Bxf6 Qxf6 8.d5 was covered in "An alternative line" whilst 6...c5 7.d5 is looked on this page.

What line is best for white ? I guess it depends on your personal skills. If you have great positional drawing skills, then the queenless endgame after 6...c5 7.d5 will suit you best. If you like to attack like a madman, then 6...c5 7.Bxf6 Qxf6 8.Bb5+ will be your normal choice.  But whatever your preference, the Blackmar Diemer gambit offers great lines for the whote player. But I guess we already new that.