Chelsea coach Jose Mourinho is upset by what he has called a lack of respect shown by France defender William Gallas in failing to report for their pre-season US tour.
Gallas, who said in May he wanted to leave the club, is in trouble after the 28-year-old did not join up with the rest of the squad in Los Angeles.
Asked about the effect of his absence, Mourinho told Sky Sports News on Thursday: "It's not only me that is upset -- we're all upset.
"Everybody is upset because we had a strong family and a strong group and this has shown a lack of respect to everybody. And I don't like that."
The club, who are considering what action to take, if any, over the no-show, have now given the Frenchman's favourite number 13 shirt to new signing Michael Ballack.
Explaining some of the background, the Germany captain said: "Initially I wanted the 13 shirt and I was sad because it had already been taken.
"I had accepted the number 19 shirt. But two days ago the coach came and said 'okay, it's fine for you to have the 13'. There was no particular reason behind the decision."
Gallas, who has failed to secure a regular slot in his preferred centre back role, is also in the middle of contract negotiations with the club.
He has a year left on his current deal.
Chelsea are expected to deploy Ballack and fellow new signing Andriy Shevchenko against an MLS All-Stars team in a friendly this weekend in Bridgeview, Illinois.
