In an astonishing turn of events, two lucky miners from the Solo CK mining pool have defied all odds and added a new block on the Bitcoin blockchain in the same week.

On Monday, a tiny miner successfully solved a block with a modest hash rate capacity of 126 terahashes per second (TH/s). Bitcoin 

BTC

$18,826

 mining expert and member of the Bitcoin Mining Council Hass McCook told Cointelegraph at the time that the odds of this happening were 1 in 1,400,000.

But according to a Thursday tweet from Solo admin Con Kolivas, another miner from the same pool was able to solve a block with a capacity of only 116 TH/s — even less than the first miner. That’s likely to be just one to three mining rigs, depending on the equipment used.

Kolivas added that the new miner joined the pool less than two days ago, “presumably in response to the other lucky block solver.”

“They’ve been astronomically lucky in solving a block solo in that time,” he wrote.

“This is insane luck at work, and a very unusual event.”

“Insane luck” might even be an understatement. McCook told Cointelegraph that the odds of this happening are so unlikely, he is unsure of how to even mathematically calculate them.

He suggested that the odds of such a small miner succeeding once was one in a million, so two successes just a few days apart would be at least one in a billion.

Related: Tiny Bitcoin miner defies massive odds to solve a valid block

When the first miner successfully solved a block, McCook said, “To say this is very rare is an understatement.”

Each of the miners, who may have been mining on just one or two machines, will take home 6.25 BTC ($266,000) for their efforts.