Botvinnik vs Capablanca chess position

30. Ba3!
White draws Black's queen away from blockading the passed pawn.
30...Qxa3 31.Nh5+! First, he sacrificed the bishop, now he gives away the knight.
31…gxh5 32.Qg5+ Kf8 33.Qxf6+ Kg8 34.e7 Qc1+
Now it is only the matter of running away from the checks.
35.Kf2 Qc2+ 36.Kg3 Qd3+ 37.Kh4 Qe4+ 38.Kxh5 Qe2+ 39.Kh4 Qe4+ 40.g4 Qe1+ 41.Kh5
Black is out of useful checks and is faced with the threat of mate with Qf8 or pawn promotion. Black resigned.