第503局 只馬當士
1 手
只马当士 — "A Lone Horse Serves as Guard" Problem 503 of 適情雅趣, volume 6 (卷六). The source gives its answer in prose rather than as a line, which is what a draw study usually needs: 「仕马保和局」 「红马当仕，黑车难胜。」 Transcribed from http://www.dpxq.com/hldcg/search/view_u_43220.html