England seamer James Anderson hobbled out of Lancashire's County Championship fixture against Yorkshire on Friday, sparking injury concerns ahead of the South Africa Test series.
Anderson pulled up midway through his sixth over at Old Trafford and went down holding his groin.
He received treatment from the physio before departing gingerly in worrying scenes for county and country alike.
Not involved with the England's limited-overs sides, Anderson's first international action of the home season is not until July 6, when the opening Test against the Proteas begins at Lord's.
Anderson left the field with figures of 1-5 from his 5.3 overs, having already taken a catch to dismiss Adam Lyth and then bowled Alex Lees.