Olly Murs has pulled the plug on his show in Glasgow, after walking off stage because he was struggling with his voice.
The singer left the 14,000-capacity Ovo Hydro venue after about 20 minutes on Thursday night, just six songs into his set.
In a video on social media after the concert, Murs offered fans an apology "from the bottom of my heart".
The 40-year-old said he was seeing a doctor before arena gigs in Manchester, Birmingham and London this weekend.
In the video posted on Instagram, an emotional Murs said: "Glasgow, I'm so sorry that I had to walk off after six songs and cancel the show.
"Most of the time as singers, you can get through it if your voice is not 100%.
"But I walked out tonight thinking my voice is great, I maybe felt a little bit run down, but I didn't think I couldn't do the show or I wouldn't have come out otherwise."
Murs said he hoped he would be fit to play his weekend shows and would update fans after medical checks.
He added: "As you can probably hear from my voice it just sounded rubbish.
"And it's unfair for you guys who spent all that money to come and see me, you deserve the best show, and me being at my best.
"Hopefully I can recover from this."
Murs said it was the first time he had walked off during a show in 15 years of playing concerts.
The singer, from Essex, rose to fame on the X Factor and went to have hits with tracks like Troublemaker, Dance With Me Tonight and Up.
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