Throw (one) a curveball American verb phrase mainly US
To surprise someone with an unexpected and difficult-to-handle problem, scenario, or inquiry.
It really threw Mike a curveball when Kim was fired.
John's death threw everyone a curveball. He paid a visit to an orphanage as recently as yesterday.
It threw her a curveball when her husband was arrested for possession of illegal drugs.
To be surprised by some sudden occurrence
To greatly surprise, shock, or confuse someone
The verb "throw" should be conjugated according to its tense.
If you take a flyer (on something), you take a chance, risk, or gamble on it.
The coach took a flyer on the young goalkeeper, and it turned out to be a wise choice.