Scans revealed that the South African quickie, signed as an interim replacement while Pakistani ace Rana Naved-ul-Hasan returns to fitness, tore his hamstring on his County Championship debut against Nottinghamshire.

The injury was worse than first feared with Morkel set to be out for six weeks and he has returned home to recuperate ahead of the Proteas' tour of England in the summer.

As a result, Rana's arrival in Yorkshire has been hastened and the Tykes are hopeful he'll arrive at the county in the next week – pending visa clearance.

Director of cricket Martyn Moxon said: "We've no plans at this moment to bring anyone else in, other than bring in Rana a bit earlier than we thought.

"We'll assess his fitness and see how close he is.

"Rana has played in the ICL and he claims he's fit, so he may well be able to switch and play straight away."

Devastated Morkel said: "I am really upset that an injury is forcing me to return home.

"Everyone at Yorkshire has made me very welcome and I was desperate to take some wickets and get Yorkshire off to the best possible start."