Flea, Chad Smith, Anthony Kiedis and Josh Klinghoffer of the Red Hot Chili Peppers perform during the Pepsi Super Bowl XLVIII Halftime Show at MetLife Stadium on February 2, 2014 in East Rutherford, New Jersey. (Photo by Larry Busacca/Getty Images)
(CNN) -- Red Hot Chili Peppers bassist Flea just gave it away, confirming what everyone already suspected.
The rock group's halftime performance at Super Bowl XLVIII was pre-recorded. The band's guitars were not plugged in.
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"When we were asked by the NFL and Bruno to play our song Give It Away at the Super Bowl, it was made clear to us that the vocals would be live, but the bass, drums, and guitar would be pre-recorded.
"I understand the NFL's stance on this, given they only have a few minutes to set up the stage, there a zillion things that could go wrong and ruin the sound for the folks watching in the stadium and the t.v. viewers. There was not any room for argument on this, the NFL does not want to risk their show being botched by bad sound, period," Flea wrote Tuesday on the band's website.
He said that he and his bandmates -- Anthony Kiedis, Josh Klinghoffer and Chad Smith -- thought long and hard about doing the show given those conditions.
"We decided that, with Anthony singing live, that we could still bring the spirit and freedom of what we do into the performance, and of course we played every note in the recording specially for the gig. I met and spoke with Bruno, who was a beautiful dude, a real talented musician, and we worked out something that seemed like it would be fun," Flea wrote.
He said the band was not trying to trick anyone.
The bassist continued: "For the actual performance, Josh, Chad, and I were playing along with the pre recorded track so there was no need to plug in our guitars, so we did not.
"Could we have plugged them in and avoided bumming people out who have expressed disappointment that the instrumental track was pre recorded? Of course easily we could have and this would be a non-issue. We thought it better to not pretend. It seemed like the realest thing to do in the circumstance.
"I am grateful to the NFL for having us. And I am grateful to Bruno, who is a super talented young man for inviting us to be a part of his gig. I would do it all the same way again."