Mate in three vs Black to move

Start Analysis Engine to see Solution #4346 Chess: 5334 Problems, Combination | Cleanchess.com | 1 Jul 2017

1014325

[Event "Start Analysis Engine to see Solution #4346 Chess: 5334 Problems, Combination"] [Site "Cleanchess.com"] [Date "2017.07.01"] [Round "0"] [White "Mate in three"] [Black "Black to move"] [FEN "8/2k5/1p1p1p2/p1pPp3/2P1Pn2/1KP1QP2/2BB1R2/r6q b - - 0 1"] 1... Ra3+ 2. Kxa3 Qa1+ 3. Kb3 a4# *

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