Nick Jonas took a tumble on stage during the Jonas Brothers concert in Boston on Tuesday night (Aug. 15).

While walking backward while singing "Sail Away," which is off the JoBros' new album The Album, Nick accidentally fell inside an open trap door.

A security guard noticeably attempted to warn Nick as he inched closer to the trap door, but his efforts ultimately failed as Nick stepped right into the open hole. The seemingly embarrassed singer took a moment to get his bearings before standing back up and continuing with the performance.

"OMG, the guard was so stressed trying to stop him," one fan tweeted alongside footage of the moment. Watch below:

Fans reacted to the moment on social media.

"Every time I watch it gets funnier," one fan tweeted.

"Shout out to the security man who tried his best to prevent Nick’s fall … Given his best shot to even catch Nick’s feet !! Very much appreciated!" someone else shared on Twitter.

"Joe in the background still singing while Nick was fighting for his life is sendinggggg me," another person tweeted.

"Not Joe and Kevin laughing at this in the background," someone else wrote.

READ MORE: Jonas Brothers Fans Are Making 'Friendship Purity Rings' for Their Tour

The brotherly trio kicked off their Five Albums One Night Tour at Yankee Stadium in New York City Saturday (Aug. 12). During the concert, the band brought out special guests including Jimmy Fallon and their former bodyguard Robert "Big Rob" Feggans, who joined them for his verse on "Burnin' Up."

The North American leg of the Jonas Brothers' tour is set to wrap up in Brooklyn, N.Y. this December.

Meanwhile, Nick, Joe and Kevin have one more show in Boston tonight (Aug. 16). Hopefully, none of them will fall (literally) victim to any more trap doors.

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