London - England spearhead James Anderson could be out of action for up to six weeks after officials announced Tuesday that the Lancashire paceman had torn his groin.
The 34-year-old, England's all-time most successful Test bowler with 467 wickets, collapsed while bowling for Lancashire against Roses rivals Yorkshire last Friday.
He was unable to bowl for the rest of the match but did make an unexpected appearance as a batsman, making an unbeaten eight off seven balls towards the end of a drawn match at Old Trafford.
Anderson is now set to miss the return fixture at Yorkshire's Headingley headquarters while medical staff at the England and Wales Cricket Board try to determine the full extent of the injury.
The experienced swing bowler no longer features for England in white-ball cricket and the first Test of the season, against South Africa at Lord's, does not start until July 7, although groin injuries can take six weeks to heal.
England chiefs would want Anderson to prove his fitness in one of Lancashire's three further Championship fixtures before the series opener with the Proteas rather than run the risk of him breaking down during a Test match.
"A scan has confirmed that Lancashire and England seamer Jimmy Anderson has a tear to his right groin," said an ECB statement issued on Tuesday.
"He will be fully assessed on Wednesday by the ECB medical team to understand the extent of his injury.
"He will miss Lancashire's Specsavers County Championship Division One match against Yorkshire at Headingley commencing on Friday June 2."