Reece James has had a precautionary scan on his knee, after feeling pain ahead of the start of pre-season earlier this week.
Chelsea expect positive news, but opted to do a scan before taking their star defender on a long-haul trip to the United States.
The 23-year-old hopes to overcome an injury-hit last season, in which he missed half of Chelsea's matches.
New Blues manager Mauricio Pochettino wants to make James integral to his plans and hopes he can build his fitness through warm-up matches against Wrexham, Brighton, Fulham and Newcastle.
James should be able to play some part in Chelsea's busy three-week tour, which will help Pochettino's slimmed-down squad be ready to face Liverpool at home on the opening weekend of the Premier League season.
Romelu Lukaku, Hakim Ziyech and Pierre-Emerick Aubameyang are not expected to make the Blues' squad, after being told they did not have to train this week, with a return date now set for Monday, when the team travels.
Chelsea hope those players, along with Callum Hudson-Odoi, who is training with the Under-21s, are sold before their return dates.
Chelsea remain in dialogue with Inter Milan over Lukaku, despite their disappointment at the latest £25.7m offer, while Fulham are confident of completing a deal for Hudson-Odoi.
