Batsman Aaron Finch may miss the rest of Yorkshire's season after suffering a suspected stress fracture in his foot.
The Australia Twenty20 captain picked up the foot injury during the T20 Blast victory over Durham on Friday.
The 28-year-old, who has scored 76 runs in six T20 Blast matches this year, underwent hamstring surgery in April.
"In a worst-case scenario, it could be the end of the season for him," director of cricket Martyn Moxon told the club website.
"He set off to run for a ball in the field on Friday and he felt a little crack in his foot.
"He's had a scan and, from an initial reading, it looks as though there's some kind of a stress reaction."
|Struggles for Finch|
|Aaron Finch has had a lean run of form since joining Yorkshire in June. His highest score was an unbeaten 73 in the Championship game against Warwickshire.|
Moxon confirmed that fellow Australia batsman Glenn Maxwell would cover for Finch if he were ruled out for the remainder of the season.
Defending champions Yorkshire have had several issues with their overseas players this campaign, with Pakistan batsman Younus Khan pulling out of a short-term deal with the club.
Khan was replaced by India's Cheteshwar Pujara, who played in the first half of the season.
New Zealand's Kane Williamson will join the club for the final three games of the Championship campaign.