Swindle!

LOST a pawn early in my round-four game at Coulsdon U2000/170 today.
The situation was even worse, both materially and positionally, later on, as can be seen in the diagram below.

Black to make his 54th move in Paul G Jackson (1778/160) - Spanton (1951/168)

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54...e4!?
Stockfish10 and Komodo10 are not keen on this at first, but give them enough time and it comes to be Stockfish10's top choice, at least for a while. Clearly Black is lost whatever is played - Stockfish10 reckons White is almost +8, while Komodo10 reckons almost +6. The point of the text, at least from a human perspective, is to try to create some semblance of counterplay - this is not a position where Black can sit tight and hope for the best.
55.Rb3 c4
Clearly not 55...Rdxf5?? 56.Rxf5 Rxf5 57.Rb8+.
56.Rb4 e3 57.Rxc4??
There are many ways to win, but this is definitely not one of them. As a general rule, it can be stated that allowing an enemy pawn to reach the seventh rank is a huge no-no unless you are certain it can be contained and quickly eliminated.
57...e2 58.Re1 Rd1+ 59.Rc1 Rd2
Black has a simple draw, once you have seen the idea of stalemate, with 59...Rc8!, eg 60.R(either)xd1 exd1=Q 61.Rxd1 Rc1+.
60.b4
This effectively concedes an immediate draw. Stockfish10 suggests 60.f6! gxf6 61.Rc7!, but it seems Black holds with 61...Rfd8! (not 61...Rd1+ 62.Ka2, eg 62...Re8 63.Rxe2!) 62.Ka2 Rb8.60...Rb8 61.Ka1 Ra8 62.Kb1 Rb8
And the game was quickly agreed drawn by repetition.