It started out as a friendly basketball game.
But things turned sour when Lee Yan Hui saw his friend being confronted by three other men.
He rushed over, punched and knocked out one of his friend's attackers.
That one punch was so violent his victim suffered head injuries and was hospitalised for 72 days, racking up a medical bill of $17,630.
Yesterday, Lee, 28, a project officer in a publishing and media company, was sentenced to eight weeks' jail for voluntarily causing hurt to Mr Chua Jun Yang, 22, on Aug 4, 2013.
Lee and his friend, Mr Mark Lim, were playing basketball at a court in Rivervale Drive, Sengkang, that day.
At about 7.40pm, when Lee was playing at one side of the basketball court, he saw Mr Lim getting into a fight with three other men at the other end.
He sprinted over to his friend's aid and saw Mr Chua punching Mr Lim.
That was when Lee punched Mr Chua on the right side of his face, causing Mr Chua to fall and hit the left side of his head on the ground.
Mr Chua remained unconscious for almost an hour.
He was taken to Changi General Hospital (CGH), where he woke up at the hospital's Accident and Emergency Department with a mild headache.
A CT scan later showed there was bleeding in his brain, among other head injuries.
His condition worsened a day later, and he underwent surgery on Aug 8, 2013.
On Oct 27, he was again admitted to CGH for another operation.
In total, he was given 21 days of outpatient medical leave.
Mr Chua paid $485 in cash, while his mother paid about $4,015 using her Medisave. The remainder of the bills were covered by medical insurance.
A medical report noted that Mr Chua's injuries were serious enough to permanently disable or kill him.
It added that Mr Chua was fortunate to make a good recovery and is able to carry on with daily activities, court papers said.
Yesterday, Lee's lawyer, Ms Ho Lifen, said her client had been practising shots at an unoccupied side of the basketball court as his friend joined a group of strangers to make up the numbers for a game at the other end.
When the fight started, Lee saw his friend surrounded by three men.
One of them punched Mr Lim while two others prevented him from escaping, she said. That was when Lee intervened.
For voluntarily causing hurt, Lee could have been jailed up to two years, fined a maximum of $5,000, or both.
This article was first published on Mar 20, 2015.
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