Adelaide, Feb 6 (PTI): Injured Australian captain Michael Clarke is still not sure about his participation in host nation's opening ICC Cricket World Cup match against England in Melbourne on February 14.

Asked if he would be available for the opening game against England, Clarke said,"I think you should ask that question to the medical staff. I don't know the answer to that question."

"I've been following their guidelines from day one and I'm extremely thankful and grateful I sit in this position now, because of their advice and guidance. I'll 100 per cent be dictated by what they feel and believe," Clarke told reporters after his arrival in Adelaide.

Clarke is hopeful that he won't have to miss enough matches after a long lay-off since the first Test at the Adelaide.

"I hope not. I've missed enough cricket over the past six months. As soon as I can get back on the park I'm keen to play every game. But if I'm told otherwise, then that's what I do," he said.

"I'd like to think once I get back on the park I'm given every opportunity to play for Australia."

Clarke scored 34 and bowled two overs in a practice game against Bangladesh yesterday but playing a full-fledged ODI is still some time away, he feels.

"Between me playing yesterday for the CA XI and walking out and playing a ODI there's still a gap - but I'll close that gap by the work I do off the field," Clarke said.

"Once I step on the field I don't hold anything back. I'll give 100 per cent. I back the work I've done.