Chris Martin has covered Taylor Swift's Love Story at a show in Vienna.
The Coldplay star gave the performance after Taylor had to cancel her Vienna shows due to a security threat.
Chris played the Love Story cover at Austria's Ernst Happel Stadium during Coldplay's already-scheduled show.
"If this is not good, please, please don't put it on YouTube because I don't want to get in trouble with Taylor," he laughed, before being joined onstage by Maggie Rogers for the performance.
The day before Taylor's three Vienna shows were due to kick off on 8 August, it was announced all performances had been cancelled after the arrest of several people who had connections with terrorist group ISIS.
"With confirmation from the government officials of a planned terrorist attack ... we have no choice but to cancel the three scheduled shows for everyone's safety," the touring company said in a statement.
On Wednesday, Taylor spoke for the first time about the cancellation, defending her decision to remain silent until now.
"Having our Vienna shows cancelled was devastating. The reason for the cancellations filled me with a new sense of fear, and a tremendous amount of guilt because so many people had planned on coming to those shows," she wrote on Instagram. "But I was also so grateful to the authorities because thanks to them, we were grieving concerts and not lives."
She added, "In cases like this one, 'silence' is actually showing restraint, and waiting to express yourself at a time when it's right to. My priority was finishing our European tour safely, and it is with great relief that I can say we did that."