Justin Bieber Covers 'Cry Me a River': Then & Now

April 17, 2012: Selena Gomez and Justin Bieber kiss at a basketball game between the San Antonio Spurs and the Los Angeles Lakers at Staples Center

Hours after if was confirmed he and Selena Gomez had broken up, Justin Bieber took to the stage at Boston's TD Garden arena on Saturday and performed one of the greatest kiss-off songs in a generation, Justin Timberlake's "Cry Me a River."

Armed with acoustic guitars, Bieber and one of his band members sat down for a passionate rendition of the 2002 classic, which was famously inspired by Timberlake's breakup with Britney Spears. Watch:

Gomez and Bieber broke up a week ago, according to E! News. "Because of their crazy schedules, it was getting harder and harder to maintain a relationship," a source revealed. Another source confirmed the breakup with the AP.

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Bieber is currently on tour promoting his "Believe" album. His next show is scheduled for Monday at the new Barclays Center in Brooklyn. Gomez, 21, is filming a "Wizards of Waverly Place" reunion for Disney.

As Beliebers know, the 18-year-old star has a lengthy relationship with the song. A version uploaded to YouTube in 2008 has been seen 20,220,065 times and Bieber mashed the track with Kanye West's "Heartless" for Billboard a year later. Watch: