Four Juniors And A German (final part)

EMBARRASSINGLY abrupt accurately sums up the finish to my round-five game at the 69th Hampstead U2200.

Black to make his 16th move in Christopher Tombolis (1914/183) - Spanton (1906/171)

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16...Rd8?
A misguided attempt not to go a pawn down. As I will show later, my main analysis engines Stockfish10 and Komodo9 reckon Black has enough counterplay to ignore the threat to c6.
17.Bxc6 Rxd1+ 18.Rxd1 bxc6 19.Ba3! 1-0
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Returning to the diagram, the engines are fairly unconcerned about Black going a pawn down. Indeed one line given by Stockfish10 runs 16...a6?! 17.Bxc6 bxc6 18.Rxc6 with the engines rating White's advantage as worth only about a third of a pawn.
However, spending a tempo to oblige White to capture on c6 seems a bit extreme. Another move given by Stockfish10 is 16...a5, when after 17.Bxc6 bxc6 18. Rxc6 the engines agree Black has full compensation for the pawn by playing 18...Kg8 or 18...a4.