John Murray vs. Kevin Mitchell moved

The much-anticipated lightweight showdown between British rivals John Murray and Kevin Mitchell was postponed on Monday because Mitchell has been battling a viral infection, promoter Frank Warren announced.

The bout was supposed to take place Saturday, but has been delayed by one week to July 16 at Echo Arena in Liverpool.

Warren moved the fight to the card headlined by junior lightweight titlist Ricky Burns' third defense against former featherweight titlist Nicky Cook.

The Burns-Cook card also features the rematch between Tony Bellew and Ovill McKenzie, who will meet for the vacant British and Commonwealth light heavyweight titles and welterweight Frankie Gavin, a 2008 British Olympian, facing Curtis Woodhouse for a regional belt.

London's Mitchell and Murray, from Manchester, were supposed to meet at Excel Arena in London. But Mitchell missed almost a week of training time because of the illness.

Warren said he returned to training last week, but needed a little extra time to make up for his down time.

"I want to face Murray when I'm fully fight fit so there are not excuses," Mitchell said.

"I've been in the gym since before this fight was announced and was on schedule with my training and in fantastic shape, but I was then hit by a virus that really knocked me back so I couldn't train," Mitchell said. "It wouldn't be fair on the paying fans and Murray if I got in the ring knowing that I wasn't 100 percent fit, so I asked Frank for a slight delay. I'll be fit and ready for July 16th and fans will see the best of Kevin Mitchell."

The remainder of the July 9 card has been canceled, Warren said.

Murray (31-0, 18 KOs), who recently relinquished the European lightweight title, and Mitchell (31-1, 23 KOs) were originally supposed to meet in April, but Warren could not finalize the deal. Murray instead made his final European title defense against Karim El Ouazghari on April 2 and won a unanimous decision.

Mitchell has not fought since May 2010, when Michael Katsidis handed him his first defeat, a third-round knockout loss in an interim lightweight world title bout in London.

Dan Rafael is the boxing writer for ESPN.com. Follow him on Twitter @danrafaelespn.