Daily Chess Improvement: Endgame Chess Tactic! Chess tactic, Puzzle Solving Black to move. How should black proceed? Source: ChessToday.net
1 rb3 and pawn queens.
a3
1… Rxb3+ This R can not be taken since 2.axb3 a3 white R can not stop the P from queening.
If 2.Kd2 Rb2+ will net another P. After 3.Kc3 Rxa2 4.Kb4 Rd2 5.Kc3 a3 can be played disregarding loss of R. Else d pawn will be lost.