Worcestershire paceman Simon Jones has suffered a blow in his comeback from knee surgery.
The former Glamorgan bowler, who helped guide England to Ashes success in 2005, took 42 first-class wickets for the Royals in nine games last season.
But after undergoing rehabilitation following an operation in September, the 30-year-old was unable to bowl in any of the county's five games during their tour of South Africa.
Worcestershire director of cricket Steve Rhodes admitted it was a blow, but remains upbeat on his star's future.
"Simon was a bit slower than we had planned and didn't get out there in a match situation in South Africa," Rhodes told the Worcester News.
"But we are keeping our fingers crossed he will be there for the first match of the season.
"The positive thing is that he is back bowling and, if we have to be a bit patient with him, that is what we'll be."
Player-coach and Australian seamer Matt Mason also picked up a foot injury in South Africa although he should be fit for the start of the season.
Worcestershire take on Hampshire at the Rose Bowl in their opening LV County Championship Division One game starting on April 15.