He was manager of Brighton when they knocked Newcastle out of the FA Cup earlier this month.
Sky Bet moved their price in from 12/1 to 6/4 in just half an hour as a wave of bets came in. Other firms in the industry made similar moves.
Former Chelsea star Poyet, currently in charge at Brighton, replaced Jose Mourinho as the market leader as a result of the gamble.
Sky Bet's Stuart Dallimore: "We had several bets around the same time for Poyet to be the next Chelsea manager, most of which were to new accounts who were hitting their maximum.
"It's hard to say whether the money is from people who know or whether it's just a bit of a bandwagon punt.
"We're still wanting to keep Mourinho fairly short as that would be the choice for the fans and the person who Abramovich should appoint if he wants to win back some of the fans."