Country star Glen Campbell showed up for the 2012 Grammy Award Show in stunning fashion, giving a memorable performance of his hit "Rhinestone Cowboy."

Perhaps making the performance even more poignant was Campbell's diagnosis of Alzheimer's disease last year. His Grammy show was his first award show since then.

Before Campbell serenaded the audience with his 1970s hit, other country artists performed some of his songs as a tribute to the Arkansas music legend.

Blake Shelton and The Band Perry sang Campbell hits "Gentle On My Mind" and "Southern Nights," doing justice to the decades-old country music that paved the way for their own success.

Then, it was finally time for Campbell's turn. The 75-year-old didn't disappoint with arguably his most famous song, "Rhinestone Cowboy." Campbell pointed the microphone to the audience so they could sing along. At the end, the crowd gave him a standing ovation.

Music may be helping Campbell in more ways than one.

"Music seems to be good therapy for [Glen]," the country music star's wife, Kim Campbell, told CNN. "We are blessed to be living in a time when there are some treatments. There is no cure [for the Alzheimer's], but there are things that can help, and they are helping."

It certainly seemed that Campbell was doing well; the four-time Grammy Award-winner finished his performance without incident.

After performing, Campbell shouted, "Thank y'all so much!"

During the extended standing ovation for Campbell, two women were spotted by the cameras sitting down, staring pointedly at their phones. Stars at the event were taken aback by the disrespectful display, and said so via social media website Twitter.

Actress Kristin Chenoweth tweeted, "Tweeting from audience rather than standing and applauding a living legend like Glen Campbell is simply rude."

Actor Todd Barry agreed, saying, "Awful women who were texting during Glen Campbell's ovation should publicly apologise (sic)."

Although the women insisted they were tweeting their love and appreciation for Campbell's rendition of "Rhinestone Cowboy," one of them still apologized for their behavior.

Campbell also earned a Lifetime Achievement Award at the show for his contributions to the sphere of country music.

This could be one of Campbell's last award show performances, as his last album and tour are already underway.

To see a video of Campbell's famous "Rhinestone Cowboy" song, click below: