A now 18-year-old man has been convicted of manslaughter in the death of a 15-year-old rugby player in 2007.

The judge in the Toronto courtroom made the ruling on Thursday morning, but reserved sentencing details until after a 20-minute recess.

Manny Castillo died a few days after receiving a head injury during a high school match in May 2007.

The Crown had argued that the young man, who was 16 at the time, committed manslaughter when he lifted Castillo into the air upside down, then drove him headfirst into the ground, causing the injury which Castillo died from a few days later.

The defence claimed her client was actually acting in self-defence when he slammed Castillo into the ground, saying he was simply protecting himself after Castillo had held him in a headlock. The defence also argued that Castillo knew that rugby was a physical sport and willingly faced the risk of the game.

They weren't involved with play when the incident occurred, the Crown argued, which the judge agreed with.

"I find there was no purpose connected with the game involved, but that it was done out of anger and aggression aggravated by the headlock incident . . . It was sucker tackle," Justice Bruce Duncan found.

The man, who is now 18, cannot be named because he was a youth at the time. The judge has suggested youth sentencing would be appropriate in the case.

CTV's Paula Todd, covering the verdict, said there was "a lot of crying and a lot of shock" in the courtroom.

Many present did not expect a conviction, since Castillo's family did not want charges pressed against the accused.

Castillo's family declined interviews Thursday saying they will wait until after sentencing to give a formal statement.