If Trump gets his way and removes Jerome Powell as chairman of the U.S. Federal Reserve, the market reaction would be swift and brutal, Deutsche Bank’s George Saravelos argues.

It could collapse the currency and bond markets, he says in a note seen by Fortune. Polymarket puts the chances of a Powell ouster at 19%.

“We consider the removal of Chair Powell as one of the largest underpriced event risks,” Saravelos says.