James Anderson faces a race to be fit for the opening Test against South Africa after scans confirmed he had suffered a tear to his right groin.
He will certainly miss Lancashire's next Championship match, the return Roses fixture against Yorkshire, which begins on June 2 but he will undergo further assessment by the ECB medical team to determine the full extent of the injury.
The first Test against South Africa begins at Lord's on July 6 and is part of a concentrated period of Test action in which England will play seven Tests by early September. Lancashire play three further Championship matches in June after the Yorkshire match which could give Anderson a chance to prove his fitness although the timescale is tight.
He pulled up during his sixth over on the opening day against Yorkshire at Old Trafford and did not bowl again in the match, although he did appear with a runner at the end of Lancashire's first innings.
This is the latest in a run of injuries for Anderson. He has missed four of England's last 10 Test matches due to a shoulder injury he picked up last summer. It ruled him out of the Bangladesh tour and flared up again in India.
Prior to that, Anderson suffered a calf injury early in the 2015-16 tour of South Africa, missing the first Test in Durban, which came on the back of a side strain sustained during the 2015 Ashes.
Before then, Anderson had only missed one Test through injury - against Sri Lanka, at Lord's, in 2011 - since his recall to the side in 2008.