New York (CNN Business) The New York Knicks were already having a rotten summer. It just got worse.

Kevin Durant, the injured star of the Golden State Warriors , is about to sign as a free agent with Knicks crosstown rival the Brooklyn Nets. That's terrible news for shareholders of MSG, the company that owns the Knicks.

MSG MSG MSG Networks MSGN Shares ofwere down about 1% Monday. And shares of, a spin-off company that airs Knicks games, fell 2.5%. Meanwhile, the broader market surged to all-time highs on optimism about a US-China trade truce.

Many fans (and investors) had hoped that the Knicks would wind up with Durant. While he'll likely miss the 2019 season because of an injury, Durant is otherwise one of the best players in the NBA.

MSG and MSG Networks shares had already been reeling since the Knicks failed to get the first pick in the NBA's draft lottery, even though they had the worst record in basketball last season.

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