Bledisloe Cup 2018: Retirement from rugby and All Blacks up to Ryan Crotty to decide - Shontayne Hape

Ryan Crotty is the only person who can decide when he gives away rugby, according league and rugby player Shontayne Hape.

Hape, who played 14 tests for the Kiwis and 13 for the England rugby team and was forced to retire in 2014 after multiple concussions, told Radio Sport the All Blacks midfielder probably had next year's World Cup on his mind.

Calls for Crotty to retire have increased since he was concussed during Saturday's first
Bledisloe test against Australia, his sixth head injury in two years.

But Hape said as a World Cup was the only thing missing from Crotty's impressive CV, it would be a strong motivation to keep him playing.

''He probably thinks he has unfinished business.

''After seeing the head knock on Saturday he will probably be spending the next couple of months off.''

But Hape would not rule out him not coming back.

''I had to wince when looked at it. I could see straight away that he was gone.

"I feel sorry for him, he has had six knocks in the last couple of years. Obviously he doesn't go out looking for them but it's just the nature of the sport. How many is enough?

''I had to realise when enough was enough as I was getting knocked out in training ... guys were not even hitting my head, just bumping into me and I was getting knocked out.

''The difference between now and then was we were hiding it. A lot of the knocks at least in today's game with the HIA [head injury assessment] are seen. Everything around concussion is monitored ... it's only a good thing for the players.''

Hape said the decision to retire came down to the player. The medical guys can only check so much and pretty much rely on the advice of what you are giving them. You have to be honest with yourself.''

Most players were honest these days because they were finding out some of the long-term effects of concussion.

''After head knocks I was struggling. I could not bear sunlight, noise and was there was nausea. My head would be throbbing like having a mean hangover for the week.''

He said Crotty would be getting the best advice possible and it was up to him how he felt.