Kwariani: Pillsbury and Albin open with an interesting variation on the Semi-Slav, avoiding the Meran which would call for ...b5.
6...Bb4 (pinning the c3 knight) is a move that belongs in the Nimzo-Indian, but here we see it transplanted into the Semi-Slav. It is interesting to note the similarities between this version of the SS and the Nimzo-Indian, specifically the Rubinstein variation (1.d4 Nf6 2.c4 e6 3.Nc3 Bb4 4.e3).
After 14.Rb1, white has gained the advantage from the opening. Black still needs to find adequate squares for his pieces, his queen is a bit awkward on h5, and the hemmed-in bishop is preventing the connection of the rooks.
Note that white could have simply played 20.Rf3, but Pillsbury had other ideas (hence 20.Qf2). The game would turn out differently, though, with 20...Bxh3 as opposed to Be6: 20...Bxh3 21.e5 Nh5 22.Rxf7 Be6 23.Rf3.
22.Nf3 preparing e5.
23.g4 seems risky, but it's perfectly sound. After ...g5??, white had 24.Qd2!, a winning shot. Black could follow with 24...Qg7 25.Nxg5 Bxa2 26.Rf1! Black could respond differently, however, in which case white would merely win differently (to echo Fischer's Bust to the King's Gambit). The eventual e5 for white is looming.
Instead of 23...g5??, c5 is safer. 24.g5 Qg6 25.Qe3 Nh7 and black is still alive.
Pillsbury's 24.e5 is premature, and after gxh4 and hxg4, Albin has managed to reach a challenging but equal position. However, this is short-lived: 26.Qg7? permits gxh5.
46...Rf6 47.f8=Q Rxf8 48.Rxf8