What Led Rihanna to Cancel Her 2016 GRAMMYs Performance: A Timeline

ET investigates what went down moments before the pop star canceled her performance during music's biggest night.

Rihanna is still feeling the heat from pulling the plug on her highly-anticipated performance at the 58th Annual GRAMMY Awards.

Moments before the 27-year-old was set to take the stage inside the Staples Center in Los Angeles on Monday, a rep for RiRi confirmed that she was forced to cancel due to being ill. Now, ET has new details on why the "Work" singer was a no-show.

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Three days before music's biggest night, the pop star-turned-fashion designer debuted her Fenty X Puma Fall 2016 collection in New York City during New York Fashion Week. She appeared excited and bright during the runway show, later taking to social media to express her gratitude to those who took part in the show and supported her along the way.

Meanwhile, in Los Angeles, ET spotted a seating card displaying Rihanna's moniker and photo inside the venue.

On Saturday, the Barbados native was in good spirits, performing on stage in Los Angeles for the MusiCares Person of the Year event honoring Lionel Richie. ET was inside and watched Rihanna belt out Richie's 1986 ballad, "Say You Say Me," which she delivered flawlessly.

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But on show day, Rihanna had low energy during rehearsals as she ran through her new song, "Kiss It Better," a source close to production later told ET. She didn't mention anything about being sick, however, only asking production if she could rehearse the song a second time before clearing the stage.

Despite reports that Rihanna had a "meltdown" during rehearsal, the production source confirmed to ET that that was far from the truth.

Less than an hour before the show started, at 4:10 p.m., Rihanna's manager told producers she was "crying in the dressing room and didn't feel well." The manager then had a doctor come to RiRi's dressing room, who diagnosed her with bronchitis and told her she could damage her vocal cords if she sang. It was then that she officially canceled her performance per doctor's orders.

"Based on Rihanna's examination after Grammy rehearsals today, Rihanna's doctor put her on vocal rest for 48-hours because she was at risk of hemorrhaging her vocal chords," the rep told ET in a statement. "The antibiotics she has been on for three days did not kill the infection adequately, therefore she cannot perform safely."

Another production source, who was involved with both planning and producing for the show, told ET that her dropping out was a complete surprise.

"Rihanna committed to performing at the GRAMMYs months ago and was excited about it," the source revealed.  "It would be her first live performance from her new album [ANTI] and she had big plans for it."

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Big plans, indeed!

As ET previously reported, James Corden -- who was set to announce Rihanna's performance -- confirmed during Monday's episode of The Late Late Show that the singer was "under the weather" during rehearsals.

Instead, the late-night host introduced Richie's tribute performance (a suggestion by GRAMMY producers), but was still bummed he wouldn't get to take part in the "cool" '80s-inspired performance Rihanna had planned. According to production, the choreography and set had a "very campy feel."

"A couple of weeks ago, I get this phone call saying Rihanna has this big thing planned for her song 'Kiss It Better' and she's doing like a whole '80s talk show thing and it's going to be really cool," Corden explained on The Late Late Show. "What she wants you to do is be like an '80s talk show host and I'd have funny glasses and I'd introduce Rihanna. She'd come out and do a song and then at the end, she'd come and sit with me, like it was it's own talk show which they called As It Lays."

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