Michael, who was number 21 last time around, has decided to switch to the number once worn by Bobby Moore, while Jermain Defoe moves from 25 to nine, and Glenn Roeder explains:
"I spoke to Michael Carrick and Jermain Defoe and offered them the opportunity to have single figure shirts; there wasn't a number nine last year and Jermain Defoe has decided to take that.
"The six is a really special shirt in the hearts of all West Ham supporters; it is amazing that at certain clubs around the world a certain number has a special meaning, normally because of a great player that once wore that shirt.
"Boca Juniors with the number 10 and Maradona is an example and the situation is that no one will ever wear that again.
"For our fans the six will always be associated with Bobby Moore, and you have to say the young man who has taken it, Michael Carrick, is destined for great things."
Of other changes, Glenn says:
"Gary Breen is going to take 15, Richard Garcia will take Michael Carrick's old 21 shirt, and there will be one or two other changes before we finally announce what the squad numbers are."
Sebastien Schemmel will be asked if he wants to move from 30, though superstition may be the overriding factor there as he won Hammer of the year in it.
Youssef Sofiane will wear 18, Raimond van der Gouw 17, Glen Johnson 23, and Anton Ferdinand will be allocated a number as well.
It is unlikely that anyone will top David Forde next season, at number 41, while 11 of last season's 36 numbered players at the end of the campaign have left the club.