Barry Zito's national anthem performance in Oakland without a mic or speakers was eerily awesome

For Earth Day on Monday, the A's welcomed back an old friend when Nashville-based singer/songwriter Barry Zito was a special guest for his former team's game against the Rangers.

Referring to Zito in his current musical form rather than "longtime pitcher" here is important, because the lefty was returning to the Coliseum to lend his vocal services for the national anthem -- with a twist. All in the name of raising awareness about energy conservation for the state of California, Zito's anthem rendition, delivered from the press box, came without microphones or speakers in the name of energy efficiency. It sounded a bit ... unusual:

Barry Zito sings the national anthem after asking everyone in the ballpark to join him without microphones or speakers on a night of saving energy celebrating Earth Day w/efforts by ex-A’s and Giants lefty and @EnergyUpgradeCA. pic.twitter.com/qNNf1PkELP — Janie McCauley (@JanieMcCAP) April 23, 2019

The A's also powered down the LED lighting on the stadium video boards for the day, as part of their #EarthDay-focused-pregame activities, which included Zito's unique return visit to the ballpark he called home for the first half of his playing career.

Oakland A’s and Energy Upgrade California to Power Down Video Screens During National Anthem for Earth Day



Team Plans to Host Energy Efficient National Anthem pic.twitter.com/6atKQyJW7q — AthleticsPR (@AthleticsPR) April 22, 2019