be out of left field informal
be from left field informal

If the offer was out of left field, the destination wasn't.

"Richie was out of left field," he said of the suspect.

Okay, that one was out of left field, al-Khaled thought.

Look, this is out of left field, but does the word Ricone mean anything to you?'

That was out of left field.

But the reports of Disney assuming the management of Starwave, this person said, "are out of left field as far as I know."

"I don't know where this story came from, but it is out of left field," said Michael J. Boskin, chairman of the Council of Economic Advisers.

Ryan Paul writes interesting articles about open source products and is a developer, so he has credibility in those areas, but his business ideas and anti-Google stances are out of left field and I frankly can't figure them out.

This was meant to be a joke, naturally, since the only pitching Bonds does is from left field in an attempt to throw out a runner, and which, with a still strong arm, he frequently succeeds in doing.