Like the Beatles told us, life is better when we get by with a little help from our friends. And when we're world-famous rock stars, sometimes that means inviting them up onstage with us in front of thousands of screaming fans — as demonstrated this past weekend by Bryan Adams, Billy Joel, Paul Simon and Bruce Springsteen.

Springsteen's set during the closing ceremonies of this year's Invictus Games in Ontario on Sept. 30 featured some support from local hero Adams, who joined him for performances of "Cuts Like a Knife" and "Badlands." Meanwhile, in New York City, Joel surprised the audience at his latest Madison Square Garden show by bringing Simon out for "The Boxer" and "Late in the Evening," followed by a joint appearance with Miley Cyrus for “You May Be Right" (which segued into Led Zeppelin's "Rock and Roll") and "New York State of Mind."

As Consequence of Sound notes, this isn't the first time Adams and Springsteen have taken the stage together — they previously teamed up at a Rainforest Fund benefit seven years ago, during which they also performed "Cuts Like a Knife." Adams captured a few moments of their pre-Invictus Games rehearsal and posted it to Instagram, writing, "What a moment to hang onto, thanks Bruce."

Joel and Simon, of course, are two of New York's most acclaimed and commercially successful singer-songwriters during the rock era, and although they haven't collaborated often over the years, Simon's guest appearance at Madison Square Garden on Sept. 30 also isn't the first time he's shared a stage with Joel. In 2015, when Joel closed out Long Island's Nassau Coliseum, he brought Simon out for a three-song guest spot.

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