The Who have postponed four concerts on their current 50th anniversary tour.

Shows scheduled for Sept. 14 at Valley View Casino Center in San Diego, Sept. 16 at the Honda Center in Anaheim, Sept. 19 at the Colosseum at Caesars Palace in Las Vegas and Sept. 21 at the Staples Center in Los Angeles will get new dates. An appearance at the Sept. 18 iHeartRadio Music Festival in Las Vegas has been canceled altogether.

The concerts are being put on hold to give singer Roger Daltrey some time to recover from an unspecified virus. The Who Hits 50! tour will resume on Sept. 24 in Portland, Ore. You can see the entire list of the band's North American dates below.

The four postponed dates were supposed to be the kickoff concerts in the Who's latest run as they celebrate their 50th anniversary of the band (only Daltrey and guitarist Pete Townshend remain from the original quartet; drummer Keith Moon died in 1978 and bassist John Entwistle followed in 2002). They previously wrapped up a series of shows in May.

Early dates on the band's tour in 2014 also got off to a rocky start because of a Daltrey illness. Two London shows from December were pushed back after the singer came down with a throat infection. The rescheduled dates will be announced in a few weeks.

In the meantime, fans can gear up for the premiere of Live at Hyde Park, a document of their London show from June 26 this year that will play theaters on Oct. 7.

The Who Hits 50! North American Tour
Sept. 24 - Portland, OR - Moda Center
Sept. 27 - Seattle, WA - KeyArena at Seattle Center
Sept. 29 - Vancouver, BC - Pepsi Live at Rogers Arena
Oct. 1 - Calgary, AB - Scotiabank Saddledome
Oct. 3 - Edmonton, AB - Rexall Place
Oct. 6 - Saskatoon, SK -SaskTel Centre
Oct. 8 - Winnipeg, MB - MTS Centre
Oct. 19 - Minneapolis, MN - Target Center
Oct. 13 - Milwaukee, WI - BMO Harris Bradley Center
Oct. 15 - Chicago, IL - United Center
Oct. 17 - Detroit, MI - Joe Louis Arena
Oct. 19 - Toronto, ON - Air Canada Centre
Oct. 23 - Pittsburgh, PA - CONSOL Energy Center
Oct. 25 - Newark, NJ - Prudential Center
Oct. 27 - New York, NY - Madison Square Garden
Oct. 29 - Boston, MA - TD Garden
Nov. 1 - Washington, DC - Verizon Center
Nov. 4 - Philadelphia, PA - Wells Fargo Center
Dec. 1 - Toronto, ON - Air Canada Centre
Dec. 4 - Louisville, KY - KFC Yum! Center
Dec. 6 - St. Louis, MO - Scottrade Center
Dec. 8 - Kansas City, MO - Sprint Center
Dec. 10 - Denver, CO - Pepsi Center
Dec. 13 - Oakland, CA - Oracle Arena

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