The All Whites vice-captain has recovered well from the problem suffered against Australia on May 24 but is not yet 100%, with officials having until 24 hours before Tuesday's opener against Slovakia to decide whether to drop him and call a replacement.

Brown admits it is a relief just to have made the trip.

"I wouldn't want to say it's a medical miracle but it's healing pretty quickly," he told the New Zealand Herald.

"I'm certainly not healed. They thought it would be a six-week turnaround and we are two-and-a-half weeks into it. But by all accounts it's going really well.

"It feels great. I hope I can hit the ground running. I have come over here to play. Obviously it's one achievement to make it to this point.

"They reckon I am about three weeks ahead of schedule and I think I have done well to get to this point but there are a whole lot of other challenges because I want to play and really contribute on the field.

"I feel like it's in pretty good shape considering. Obviously there's a wee way to go but hopefully that will be pretty rapid and I will be training and playing at full speed pretty soon. I'm feeling pretty good and I'm confident I will be training fully pretty shortly.

"In my mind I can get into training pretty soon. As for this game on Tuesday, we will have to see."