It’s never a good idea to save 22 seconds for the endgame. In fact, it’s a much better idea to save at the very least half an hour for it.
37.f4+! Looked like an easy enough win, but as I found and showed Mekonnen after the game I had to be wary of in-between shots. I showed him 37…Kxf, 38.Nxd6 (it’s this pawn that I had underestimated) Ke5, 39.NxBb7 and now the knight is pinned to the rook and the rook can only escape with check. But Fruit shows that it is winning because the White king wheels around via a4 and pushes the e-pawn with king while Black gobbles up White’s kingside pawns, but cannot promote in time (I didn’t even look that far, but it’s a deep line!). Okay, I followed the line 25 moves deep. White promotes the c-pawn and checkmates Black where Black’s king is on h1 and Black’s passed pawn is on h2, one square from queening, but actually help-mating it’s own king. BTW, 39.Rxb7 is also winning, but it’s a queen and pawn vs queen ending where there is still an equal line and a winning line.
Anyhow, I took his g5 pawn instead because I figured it’s a safe pawn and should be enough, but it still takes a delicate touch to win this ending, and that is not something which I saved any time for.
An easy win is the plan 45.Nb1, 46.Na3, 47.Nb5 with an unstoppable win, but a move like 45.Nb1 does not come off of the top of most people’s heads. Still, if there had been a second time-control at move 40 (not that I should ever expect one), it would have been a slam-dunk to find this sequence.
47.h5! is another slam-dunk win as the bishop is now baby-sitting the g4 pawn instead of attacking White’s backward c3 pawn. The h-pawn push peels the Black king away from defending the backward d6 pawn.
65.Ng5!! looks like a position I had on the board, but you don’t find this shot with 5 seconds on your clock. In fact, after 65.Nf6+, I got two minutes added to my clock because he moved his pawn instead of moving out of check, but I would take a winning position with 5 seconds as the two minutes was wasted looking for something that wasn’t there.
It’s hard to say whether I had a win or loss in the endgame because my opponent, as happened last night, stopped keeping score when I did, in my time-pressure.