A fellow attendee to the Hollywood party told Us Weekly the couple posed together on the red carpet, and Lambert went inside while Shelton did his interviews.
They laughed off the rumors on Twitter earlier this week, with Shelton tweeting to his wife: "Hey @mirandalambert... I just read in a tabloid that our marriage is falling apart!!! FOCK!!!"
She replied: "Oh no! Can't wait to read if we make it or not"
Shelton, 36, and Lambert, 29, married in 2011. Us described a "slew" of tabloid articles accusing Shelton of cheating on Lambert with aspiring singer Cady Groves.
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