[FEN "r3r1k1/6p1/p1pq3p/1p1p1p2/PPbP1P2/2Q1P2P/6P1/RN2R1K1 b -"]

26... a5 27. bxa5


w b wb bw | w b wb bw

b     an
    


26...a5      an
    


27. bxa5      an