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Clearly, tension in this game revolves around white's effort to promote the well-supported c-pawn, and black's effort to counter that threat.

Black faltered with <62....Rf2?>. Black intends ...Rf8 to guard the promotion square, but after <63.c6!> the N and P effectively keep the king at bay, and the white king has time to step up to assist the pawn push.

A better bet for black would have been to just keep giving checks from the h-file, i.e. 62...Rh3+. What can white do? He basically has 3 choices:

1. Escape checks by approaching the rook (e.g. 63.Ke4 Rh4+ 64.Kf3 Rh3+ 65.Kg2)

2. Escape checks by heading for c1 (the LSB prevents the rook from giving check at h1, and at c1 the king prevents the rook from attacking any of white's pieces)

3. Escape checks by heading for a5.

With the first two approaches, the white king is drawn away from being able to support his c-pawn. This gives the black rook time to defend successfully, either via the f-file (heading for f8) or attacking white's pawn or pieces from the rear.

With the third approach, the game continues, 63.Kc4 Rh4+ 64.Kb3 Rh3+ 65.Kb4 Rh4+ 66.Ka5 [diagram B]

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And black can counter with 66...e4!, creating her own promotion threat. If both pawns promote, it's a draw (note that black's pawn promotes with check). If white makes an effort to stop black's pawn (e.g. 66...e4 67.c6 e3 68.Bf3), then black has the opportunity to defend successfully with 68...Rc4.

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The game progressed, <63.c6! Rf8> [diagram C]

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Here, white made a mistake with <64.Ke4?>. Rather than worry about black's pawn, White should have played 64.Kc4 with Kc5 in view to support the c-pawn promotion.

This mistake gave black one more chance to get a draw, ...if black finds the right defense.

It continued <64...h5!> creating a promote-with-check threat with the h-pawn <65.Kxe5 Rf5+ 66.Kd4> [diagram D]

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Unfortunately for black, she continued with the same mistake she made on move 62, <66...Rf8?> allowing white to finally play <67.Kc4!> and win.

What black needed to find was 66...h4! 67.c7 Rxd5+! 68.Kxd5 Kd7! and it's drawn. [diagram E]

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The white K can chase the h-pawn, but since the h-pawn can be guarded by the g-pawn, the K can never help promote the c-pawn. Or, the white K can support the c-pawn via 69.Kc5, 70.Kb4, 71.Na3 and 72.c8=Q, but in that time the black h-pawn also promotes and it's still drawn.

Note that the move order matters in this last line. That is, in Diagram D, black must play 66...h4 first.