Paolo Nutini delighted thousands of fans on the opening day of TRNSMT - just hours after topping the charts with his first album in eight years.
The singer was given a rapturous welcome at Glasgow Green as he took to the stage for Friday's headline slot.
Scotland's largest music festival is back to its traditional summer date after two years of Covid disruption.
US rockers The Strokes top the bill on Saturday while Lewis Capaldi is the main attraction on Sunday.
On Friday evening festival organisers confirmed that Years & Years would not perform on the main stage on Saturday, as singer Olly Alexander has a virus.
Last week Paisley-born Nutini released Last Night In The Bittersweet and on Friday it was confirmed he had scored his third number one album.
The Bootleg Beatles got TRNSMT under way on the main stage on Friday and were followed by stars including Tom Grennan, Nile Rogers & Chic and Sam Fender.
About 50,000 people are expected to attend the event at Glasgow Green on each of the three days.
This year's weekend line-up also includes Foals, Fontaines DC, Wet Leg and Wolf Alice.
TRNSMT organisers have advised those attending not to travel by car as there is no parking available and surrounding roads will be closed.
They also warned that rail travel could be hit by last-minute cancellations and extremely limited rail services across Scotland.
This is due to a temporary timetable currently in place after a pay dispute which could mean some struggle to get a train when the festival ends.
On Sunday night, when Scots singer-songwriter Lewis Capaldi is set to close the festival at 23:00, there will be no trains when fans leave.
The first TRNSMT festival took place over three days in July 2017. It was widely seen as a replacement for T in The Park, which was run by the same promoters and operated in the same July timeslot for 23 years until 2016.
In 2020, TRNSMT was postponed because of Covid and in July last year it was delayed again because of concerns over spread of the virus.
It eventually took place from 10 to 12 September 2021.