England captain Dylan Hartley would consider calling time on his career if he was to suffer another concussion before next season.
A collision with Billy Vunipola in Northampton's Premiership meeting with Saracens in November resulted in Hartley being concussed and he sustained another following a blow to the head in England's Six Nations victory over France in March.
The hooker has since only played one competitive match and he admitted that a repeat incident in the Test against Wales or tour to Australia would make him seriously consider his future.
"If I got another [concussion] now I would be worried," said Hartley.
"I would probably start looking at other careers or maybe a long layoff. Maybe I [need to] look at my tackling technique, too.
"But it's not something I fear. It is something you deal with when it happens. I won't go into the weekend worrying about it and feel strong and fit. I feel confident in my head and have tested it out a few times."
It was difficult for Hartley to find motivation during his recovery, adding that becoming a father has given him a fresh perspective.
"I couldn't run, I couldn't do anything. It was lethargy, constantly wanting to sleep," said the captain.
"I had no urge to get on the bike. I almost tried forcing myself to get on and I just said 'I can't be bothered', so I went back to lie on the couch and went to sleep.
"There's no lying in your recovery. I had a constant reminder of that every time you see your kid and you think 'if I hit my head again, what's that going to mean?'
"Three in one season would warrant a bit of time off and I probably would take a step back and have a minute."