Is it genuinely possible for white to checkmate black in this position?

I played this game, and white was awarded the win, but I'm unaware of how white could even win this position - is it not draw by insufficient material?

I think the only way is with bishop under promotion.

Underpromotion to a knight works as well:

Here is a faster checkmate with bishop under-promotion:

@Karlakshman said ^

I played this game, and white was awarded the win, but I'm unaware of how white could even win this position - is it not draw by insufficient material?

https://lichess.org/game/RVW1IHwU/black

Screenshot 2026-10-27 at 5.37.08 PM.png (https://image.lichess1.org/display?fmt=png&h=0&op=resize&path=LYCpCabxEsh0.png&w=864&sig=28f616a9f1906184438a2d9117bf559e5028615f)

White truly lacks sufficient material to deliver a forced checkmate, but if they come to an agreement with their opponent, they can achieve a "cooperative mate." This is the most controversial point in the rules.

In other words, if someone were to actually promote a pawn to something other than a queen or a rook—and then end up in a checkmate position—the players would be accused of collusion. It’s that absurd.

"a forced checkmate"

• The Laws of Chess stipulate any series of legal moves leading to checkmate.
  Generally if you lose on time, then you lose... on time.
  There does not have to be any forced checkmate.
  If you dislike that, then play with increment, so you have time to demonstrate your defense.

@tpr said ^

"a forced checkmate"

• The Laws of Chess stipulate any series of legal moves leading to checkmate.
  Generally if you lose on time, then you lose... on time.
  There does not have to be any forced checkmate.
  If you dislike that, then play with increment, so you have time to demonstrate your defense.

The rule implies that a "cooperative checkmate" is possible.
I was simply explaining the difference between a forced checkmate (queen versus bishop) and a cooperative one (bishop versus bishop).
The rule isn't intended solely for cases where someone runs out of time, is it?
That is precisely where the absurdity lies.
Or are you saying that if someone gets such a cooperative checkmate while having time increment, he will break the rules of chess?

with sufficient increment the other player can play till 50 moves is reached or opponent hits the pawn. So most likely in such a case opponent would even agree to draw.

@petri999 said ^

with sufficient increment the other player can play till 50 moves is reached or opponent hits the pawn. So most likely in such a case opponent would even agree to draw.

Look, either we discuss recommendations and conjectures, or we discuss the rules as they actually exist.
The rules simply state that one must stay within the allotted time.

"The rules simply state that one must stay within the allotted time."

• Yes, if you time out, then you lose.
  However, you cannot win on time when there exists no series of legal moves to win on the board.