Sydney - Australia batsman Phillip Hughes was undergoing emergency surgery in a Sydney hospital on Tuesday after suffering a sickening head injury when struck by a short delivery during a domestic first-class match.
VIDEO:Phil Hughes critical after being struck by bouncer
A spokeswoman at St. Vincent's hospital said the 25-year-old was in critical condition and had been taken into surgery after being rushed from the Sydney Cricket Ground where he had been batting for South Australia in a Sheffield Shield game.
"He's suffered a head injury ... He's currently in surgery right now," the spokeswoman said. "We are unable to give an estimate on how much time it will take."
Hughes was given mouth-to-mouth resuscitation by medical staff and treated on the SCG boundary for about 40 minutes after he was struck by a short-pitched ball that reared up into his helmet from New South Wales fast bowler Sean Abbott when on 63.
He arrived at hospital in an induced coma and underwent scans before he was taken into surgery, a hospital spokesman said earlier.
Fast bowlers regularly deliver the ball at speeds of over 140kph. A cricket ball is roughly the same shape and size as a baseball but heavier and harder.
They occasionally strike batsmen on the helmet, and often draw blood on impact, but the seriousness of Hughes's injury shocked seasoned cricket writers and players alike.
Dazed after being hit, the left-hander put his hands on his knees before falling face first onto the pitch, causing players and medical staff to rush to his aid.
Hughes was taken from the middle on a motorised stretcher before being treated on the boundary. A helicopter landed at the ground but Hughes was taken to hospital by ambulance.
The match was called off for the day.
Australia captain Michael Clarke arrived at the hospital to check on Hughes' condition, while Hughes' mother and sister were also at the hospital.
South Australia Cricket's high performance director Tim Nielsen later issued a statement on behalf of the family.
"As you all will be aware Phil Hughes suffered an injury this afternoon," the statement read.
"He is presently undergoing surgery and the outcome of that surgery is unlikely to be known in the next 24-48 hours.
"In the meantime, we would really appreciate if you look after his family and friends and respect their privacy please."
News of the injury sparked a wave of sympathy from the global cricketing community and fans on social media.
"Our thoughts and prayers are with phil and his family! He is a great fighter and a great young man!" Australia coach Darren Lehmann tweeted.
Hughes, who has played 26 test matches and 25 one-day internationals for Australia, was touted as a potential replacement for the injured Clarke for the first test against India in Brisbane next week.