Doctors have shut down the on-going Who Hits 50 tour after Roger Daltrey contracted a throat infection. He's been ordered to rest, pushing back the last 2014 dates of the tour, which were originally scheduled for Wednesday and Thursday (Dec. 17-18) at the O2 Arena in London.

"The band and their management wish to sincerely apologize to all ticket holders for the inconvenience and disappointment this has caused," the Who said in a statement.

Both shows have already been reset for March 22-23 of 2015. All tickets will be valid on that dates, with refunds available now at the point of purchase.

The rescheduled concerts will arrive in advance of the Who's June dates at Hyde Park, as part of the British Summer Time Festival. That appearance has been announced as the finale on the Who Hits 50 tour, which could be the band's last.

The Who issued 'Get Lucky,' their first new music in nearly a decade, back in September. The song was included as part of the band's new double-disc 'Who Hits 50!' collection. More recently, the group released a new 'Immersive App,' designed by Daltrey's son Jamie.

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