According to Latics chairman Dave Whelan, the Blues have already had three bids rejected for the player.
However, Moses only has a year left remaining on his contract at the DW Stadium and Wigan could risk losing him for nothing should he decide to see out the remainder of his contract.
“[It’s] something that the clubs are discussing but at the moment he is a Wigan player,” he told reporters.
“He had a good season last season, he is young and an interesting prospect.”
Chelsea have been linked with several big-name players this summer but Di Matteo is also looking to offload players and sees pre-season as the perfect opportunity to evaluate his squad.
“We cannot name more than 25 players in the squad so we will have to make some decisions,” Di Matteo added.
“Pre-season gives me a great opportunity to look at the new players and see how they develop. The final decision on who will go and who will stay will be made at the beginning of August.
The Blues manager was impressed by new signing and goal scorer Eden Hazard in Chelsea’s opening game of their tour of the United States against Seattle Sounders, which they won 4-2.
“Hazard is a versatile player,” he added. “He can play in a role behind or out wide and last season we didn’t have too many options apart from Juan [Mata] so it is great for the club to have different options.”