Metrodome - May 4, 1984

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Oakland’s Dave Kingman — one of baseball’s all-time feast-or-famine hackers — hit a pop-up off lefthander Frank Viola that was so high that it went through a hole in the roof of the Dome and never came down.

Hrbek was out because of an injury but watched as his replacement, Mickey Hatcher, and other Twins players looked up at the Teflon roof in befuddlement.

“Literally, we had lost the ball,” Hrbek said.

The Dome was known for its quirks. There was a blind spot down the left-field line, so outfielders had to keep running until they picked up the ball again. Home runs were thwarted by the baggie in right. And plenty of pop flies clanged off the speakers that were attached to the roof. The most famous speaker-ball was in 2000, when the Angels’ Mo Vaughn thought he had hit a long two-run homer, only to see the ball hit a speaker and carom to the field for a no-run single.

Many felt it was a matter of time before a ball would disappear into one of the holes in the Dome’s roof. The holes were part of a drainage system that, by design, would keep the Dome from collapsing under heavy snow (I know, I know).
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http://www.startribune.com/sunday-insider-three-decades-have-passed-since-dome-ball-disappeared/257822871/