(Bloomberg) -- It was supposed to be a quiet trading day in the U.S. that could easily be handled through post-Thanksgiving drowsiness. Instead, news spread Thursday night of an ominous new coronavirus variant, and traders braced for widespread losses on Black Friday. 

In a rush of adrenaline that recalled the dark days of March 2020, Craig Erlam, a senior market analyst at currency trading and data firm Oanda, had to jettison his plans.

“I knew how it was going to go, I was going to pick up the kids from school,” Erlam said. “Then suddenly everything turns on its head, you get a lot more phone calls. It’s certainly been a much more dramatic end to the week than I’d hoped.” 

Even eating and drinking was an afterthought for Erlam.

“I let my coffee go cold,” he added. “In fact, I don’t think I’ve managed to drink a cup of tea or coffee when its been warm all day.”

Markets were hit around the world. The S&P 500 fell 2.3%, it’s biggest one-day decline since February, with more than 470 of the stocks in the index down. Stock indexes also declined in China, Japan, the U.K., France, and Germany, among other nations. Commodities from copper to crude oil to cotton all dropped. Safe-haven U.S. Treasuries surged.    

Jay Hatfield, chief executive officer of Infrastructure Capital Management, was ready Friday morning because futures were tanking Thursday night. It didn’t make trading any easier. 

“This could be the worst of it, but it’s not like I’ve traded 100 pandemics on the day after Thanksgiving and that always happens or something,” he said. 

Since David A. Katz, chief investment officer at Matrix Asset Advisors, normally works from 5 a.m. until 6 p.m., he “was hoping to wind down earlier.” Sorry -- not this Friday. 

“I’ll work a full market day because it’s going to be active,” he said. 

Not everyone found the day to be painful. Some were positioned for market declines at least at some point. 

“We are net short today so I’m grateful personally,” said Max Gokhman, chief investment officer at AlphaTrAI, a long-short hedge fund.

And others had been waiting for a good time to buy. 

“This is kind of like my stock Black Friday,” said Kim Forrest, chief investment officer and founder Bokeh Capital Partners. “I think in the short term -- six months to a year -- some things were ahead of themselves, and I just couldn’t pull the trigger. And these sell-offs like today, give me opportunity to fill in the portfolio.”

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