All in the Middleton

Tom Middleton raised to 400 in middle position and was called by the two players on his left: Jonny Horn and Robert Butt. A flop of J 5 6 is checked to Butt who bets 1000. Back to Middleton who moves all-in for around 3500. After some deliberation Horn called and Butt got out of the way. Middleton’s A K were way behind Horn’s 6 6 for middle set. The impossible did not happen when turn and river came 9 3 and Middleton hit the rail.