James Anderson is facing an extended spell on the sidelines after the England and Wales Cricket Board announced the seamer has torn his groin.
The 34-year-old, England's leading Test wicket-taker with 467, collapsed in pain on Friday while bowling for Lancashire against Roses rivals Yorkshire.
He was unable to bowl for the remainder of the match but made a surprise appearance with the bat, making eight not out in seven deliveries at the end of the drawn encounter at Old Trafford.
Anderson will miss the return fixture at Headingley while the ECB's medical team attempt to determine how bad the injury is. The first Test of the summer is not until July 7 at Lord's, after the Champions Trophy, leaving plenty of rehabilitation time but it is not uncommon for such complaints to come with a six-week lay-off.
Lancashire have three further Championship fixtures before the first Test and Anderson would need to play at least one at full tilt to prove his conditioning to the selectors.
An ECB statement read: "A scan has confirmed that Lancashire and England seamer Jimmy Anderson has a tear to his right groin. 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."