I've seen markets move a few ticks (a tick = one price movement, eg 1.87 to 1.86) in the opening minutes, but this is ridiculous.
Australia v Uzbekistan, live on Eurosport and around Australia. Two mins before the match, under 2.5 goals was 1.78 (where the last big grey column is on the graph). At 4:50 gone, the price had collapsed to 1.58! That's twenty ticks in under five minutes! Money for jam if you know what you're doing and don't get too greedy.
Six minutes later and the price change had slowed down, to only 1.5.