Player draws seven, chooses to mulligan.
After reshuffling, player lays seven cards on the table, face down.
They look at four cards, then realize the mistake.

What do you do?

Put one of the face-down cards back.

d:^D

Originally posted by Scott Marshall:

Put one of the face-down cards back.

d:^D

Since you're here, Scott. How about if the opponent says “hey, but they've already drawn what was the seventh card laid out.”?

My understanding is “random is random”, so the actual card (whether it was the first or the seventh) being returned doesn't matter, just as long as it wasn't seen.

Originally posted by Chris Wendelboe:

My understanding is “random is random”

That's the correct philosophy here, Chris. Unless we're dealing with Marked Cards, there's no advantage to drawing the 2nd - 7th instead of 1st-6th cards off the top of the library.

Back in the days of Drawing Extra Cards, we had language in the IPG that made it clear that counting out cards face down was not the same as drawing them. Technically, those other three cards - the ones that haven't yet been drawn, nor seen - are still part of the library.

d:^D

I had this issue come up for me at a PPTQ I helped Judge at. He drew 7 cards and looked at the first 3, the ones that would have contained the 7th card. Both players had agreed and I had ruled it as either shuffle the full 7 away and go right to 5 cards or he may have the opponent look at the 3 that the player saw and shuffle one of them into the deck before going to normal mulligan procedures.

Originally posted by John Farquhar:

I had this issue come up for me at a PPTQ I helped Judge at. He drew 7 cards and looked at the first 3, the ones that would have contained the 7th card. Both players had agreed and I had ruled it as either shuffle the full 7 away and go right to 5 cards or he may have the opponent look at the 3 that the player saw and shuffle one of them into the deck before going to normal mulligan procedures.

Hi John, I can definitely see how you got to that conclusion and I think it's a reasonable place to land up. Check for shenanigans (marked cards, ask some questions about why they did that) of which there are likely not many; this would be a weirdly specific cheat! Once that's done, we then use the philosophy Scott has underlined above; they've drawn 3 random cards and they only need 3 more, so put one of the unseen cards back. :)