A Brazilian Beatles fan proposed to his girlfriend with a little help from his friend -- Sir Paul McCartney himself!

An audience member at McCartney's concert in Fortaleza, Brazil last Thursday had been holding a sign that said, "Paul, I want to propose to my love onstage. Would you bless us?" So McCartney paused the show for a few minutes to give these superfans an unforgettable engagement story.

"Listen, we have a special thing tonight. One of the signs in the audience was for a boy and a girl. And the boy said he wants to propose to his girlfriend onstage. What do you think? Yeah?" McCartney said, giving the thumbs-up sign. "We gotta do it."

The couple came onstage and, after a little prompting from McCartney, the groom-to-be got on one knee, pulled out a ring, and popped the question in Portuguese.

After she said, "yes," McCartney enveloped the couple in a group hug.

"Oh yeah, that's a first," he quipped.

Watch the proposal in the video above (posted to YouTube on Tuesday).

For music fans, there's probably no better way to propose than onstage at a rock concert. Keyshia Cole facilitated an onstage marriage proposal at a concert in March, and Foster The People also let a couple get engaged onstage at a concert in 2012.

Check out 10 of the best proposals of all time in the slideshow below.

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  • Downtown Disney Flash Mob

    Jamin brought a little Disney magic to his proposal when he <a href="http://www.youtube.com/watch?v=Su1YLAjty-U" target="_blank">organized a flash mob</a> in Downtown Disney in 2011.

  • "Julie Will You Marry Me" Website

    In 2011, Jim worked with an artist to create a comic strip-like history of his and Julie's relationship, which ended with a marriage proposal. He posted the drawing on a <a href="http://www.huffingtonpost.com/2011/07/19/cutest-marriage-proposal-ever_n_903657.html" target="_blank">website</a> and filmed Julie's reaction as she read it. Click <a href="http://juliewillyoumarry.me/" target="_blank">here</a> to see the adorable website, and watch the video at left to see Julie's reaction.

  • Romantic Proposal On A Dock

    Do proposals get any more romantic than this? In 2011, Tyson <a href="http://www.youtube.com/watch?feature=player_embedded&v=TECPJI6Z2gs" target="_blank">led his girlfriend, Michelle, to a picturesque dock</a> in Oregon, where their friends were waiting with flowers. They were serenaded by a guitarist as the groom-to-be popped the question.

  • Buzzfeed Meme Proposal

    Len Kendall has the entire internet to thank for helping him pop the question to his girlfriend, Katie, in 2012. Kendall posted a meme-like photo of himself (look left) proposing to Katie on <a href="http://www.buzzfeed.com/lenkendall/help-me-convince-katie-to-say-yes" target="_blank">Buzzfeed</a>, and started a Facebook group, Pinterest page and Twitter hashtag #SayYesKatie to urge others to create their own memes asking Katie to marry him. Click <a href="http://www.huffingtonpost.com/2012/02/29/say-yes-katie_n_1310729.html#s740651&title=Len_Kendalls_Proposal" target="_blank">here</a> to see some of the best memes created for Len and Katie.

  • Madison Square Park Proposal

    One man pulled out all the stops for his proposal in a park in 2010, including <a href="http://www.youtube.com/watch?feature=player_embedded&v=bQVoAWSP7k4" target="_blank">dancers, huge signs, a unicycle, and streamers</a>. After she said "yes," the happy couple rode off in a horse-drawn carriage.

  • White House Gay Marriage Proposal

    U.S. Marine Corps captain Matthew Phelps and his partner, Ben Schlock, made history in 2012 by becoming the <a href="http://www.huffingtonpost.com/2012/12/17/white-house-gay-marriage-proposal-_n_2317455.html" target="_blank">first gay couple to become engaged at the White House</a>. Phelps told HuffPost that he wanted to propose at the White House because they had their first date there, at the LGBT Pride Month Reception, six months earlier.

  • Isaac's Live Lip-Dub Proposal

    In the <a href="http://www.huffingtonpost.com/2012/05/29/portland-proposal-video-e_n_1554435.html" target="_blank">first viral lip-dub proposal</a> (but <a href="http://www.huffingtonpost.com/2012/10/01/epic-lip-dub-proposal-brad-emily_n_1929700.html" target="_hplink">not the last</a>), Isaac Lamb had his girlfriend sit in the back of a truck as they drove through a Portland park, then played Bruno Mars' "Marry You" while dancers popped out and lip-synched to the song. The proposal, which took place in May 2012, now has more than 18 million views on YouTube.

  • Meme Proposal

    Tim Tiah proved just how useful those popular internet memes can be when he proposed to his girlfriend, Audrey, in 2011. While Audrey was at a restaurant with friends, Tiah stood outside and <a href="http://www.huffingtonpost.co.uk/2011/12/22/meme-filled-marriage-proposal-video_n_1164674.html#s567043&title=Song_And_Dance" target="_blank">held up signs containing memes</a> that corresponded to their relationship, ultimately using the <a href="http://www.quickmeme.com/Puss-in-boots/?upcoming" target="_blank">Puss In Boots meme</a> to pop the question.

  • Fake Movie Trailer

    Back in 2011, Matt Still convinced his girlfriend, Ginny, to go to the movies one day -- then, he arranged to <a href="http://www.youtube.com/watch?feature=player_embedded&v=pnVAE91E7kM" target="_blank">play a fake movie trailer</a> before the movie that chronicles his journey to the theater to pop the question.

  • "Mobbed" Flash Mob

    In 2011, <a href="http://www.fox.com/mobbed/" target="_hplink">Fox T.V. show "Mobbed"</a> featured an epic marriage proposal. Groom-to-be Justin <a href="http://blog.weddzilla.com/topics/getting-engaged/get-mobbed-on-fox/" target="_blank">recruited 1,000 people</a> to participate in an over-the-top flash mob for his girlfriend, Nikki.

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