Concerns as All Blacks superstar Barrett suffers another head injury

All Blacks superstar Beauden Barrett suffered another head injury after a bone-crunching collision in a Super Rugby match on Saturday ended with the flyhalf leaving the pitch with blood pouring from his nose.

Barrett, 30, was making his first start for the Blues this season having suffered a concussion in a Test match against Ireland in November, an incident which he thought could end his career.

The playmaker was escorted off the pitch in Dunedin early in the second half after a high-speed clash with Highlanders centre Fetuli Paea.

Barrett underwent a Head Injury Assessment (HIA) but was not allowed to return to the match and was replaced by Stephen Perofeta who saw his team home to a 32-25 victory.

Blues coach Leon MacDonald said that they were not prepared to take risks with Barrett's health.

"It was a no-brainer. He got a good contact to his face - that's why he's got a bleeding nose," MacDonald was quoted by rugbypass.com.

"We're never going to take any chances with Beauden, we want to look after his health and make sure he's well."

He added: "They were brutal carries and their clean-outs were ferocious in the second half and Barrett was on the end of one.

"He's got a good fat lip and a bleeding nose and hopefully it's nothing much more than that. We'll have to track him and see how he cleans up."

Barrett complained earlier this year of serious migraines in the aftermath of his injury in Ireland.

"I thought it might be the end of my career. When you feel sluggish 99% of the day, trying several ways to get better but nothing works, you are planning for the worst," he said.

"And then you hear about team-mates having to end their careers because of concussions, it's more and more frequent. I thought it was my turn."

Barrett has