The chief executive of Glasgow 2014 has apologised after sports fans faced delays while trying to snap up the latest release of Commonwealth Games tickets online.
David Grevemberg told the BBC it was "totally unacceptable" that people had to wait hours while trying to buy seats.
People who previously missed out on tickets and any last-minute buyers were given a chance to secure seats for this summer's event from 10am yesterday on a first come, first served basis.
But Glasgow 2014 organisers had to apologise for delays and difficulties yesterday after they were overwhelmed with demand for tickets.
They announced they would close the website for an hour last night for investigations.
Speaking on BBC Radio Scotland toda,y Mr Grevemberg apologised for the problems.
He said: "We let a lot of people down, which we are very sorry for. It was an incredibly frustrating and disappointing day yesterday.
"It's just not in keeping with the experience we are trying to create with Glasgow 2014. To put it simply, the system just did not cope.
"Despite being fully tested, it just did not cope with the churn."
He described it as "totally unacceptable".
The extra tickets across all 17 sports and the opening and closing ceremonies became available as the final arrangements for venue layouts and spectator seating were made, Games chiefs said.
About 2.3 million applications were made for the initial one million tickets released last year, with athletics, aquatics and cycling proving the hottest tickets.
The Games were given a boost yesterday when double Olympic gold medallist Mo Farah confirmed he will compete this summer.
The addition of Farah, who took to Twitter to make the announcement, is likely to further fuel the demand for tickets, which organisers have said is ''unprecedented''.
The 31-year-old athlete told his one million followers: ''Hi guys! I will be running in the Commonwealth Games this year..!! See you in Glasgow..!! Shabba....!!''
Farah, known for his trademark Mobot head gesture, has not yet revealed which events he will compete in at Hampden Park.
It is possible he could attempt the same double he achieved in the Olympic Stadium in London 2012 in the 5,000m and 10,000m, or he could decide to compete in just one of those events.
But it is unlikely he will attempt the gruelling task of running the marathon after his coach Alberto Salazar advised him to forget about the discipline until after the 2016 Rio Olympics.
A statement on the Commonwealth Games website said: "As traffic has increased, we have seen some recurrence of issues people were having with the ticketing website.
"We are continuing to sell tickets, but at the same time we need to investigate the cause of these issues and monitor the queue closely.
"We will provide an update on this website and our social channels on a regular basis."