Former Canterbury and West Tigers winger Matt Utai was hospitalised after being shot multiple times outside his home in Greenacre, in southwest Sydney, as he was about to drive to work on Tuesday morning.
Police linked the shooting to his son Iziah Utai's alleged criminal associations and escalating gang conflict.
Shots were also fired at a home in outer western Sydney about 12.45am on Wednesday before a firebombing was carried out in Guildford West, near Parramatta, hours later. A woman in her 50s who was inside the first home was uninjured.
All incidents were targeting the Utai family, police said.
Bulldogs coach Cameron Ciraldo, whose playing career crossed over with Utai, said the club was praying for a quick recovery.
"He's obviously a beloved Bulldog" he told reporters on Thurday.
"I have been in touch with a couple of his teammates in recent days and we're all praying for his health and safety and really hoping he pulls through.
"I know he's got a lot of support from our club, and in particular all the players he played with, they all love him."
Four people were charged over the spate of attacks after police searched six properties across Sydney's southwest and western suburbs.
A 19-year-old man was arrested in Guildford for allegedly picking up the gunman after Utai was shot.
He was charged with being an accessory after the fact to a shooting with intent to murder, along with participating in a criminal group and a drug charge.
A 16-year-old boy police allege handled the gun was also charged with being an accessory after the fact to a shooting with intent to murder and supplying a pistol to a person unauthorised to posses it.
Both were refused bail to appear in court on Friday.
An 18-year-old man arrested in Riverwood was charged with damaging property by fire and participating in a criminal group, accused of the firebombing in Guildford West. He was bailed to appear in court on March 10.
Another 19-year-old man was charged with participating in the criminal group related to the firebombing and commercial quantity drug supply after police allegedly found 1kg of cocaine at this house.
Utai had surgery after being left with serious leg wounds from the attack.
Unverified footage of alleged offenders taunting the younger Utai before firing off several shots have circulated on social media.
An underworld-focused media outlet also reported the Alameddine crime family was "at war" with a group dubbed the Coconut Cartel, sharing a message purportedly from the "one and only crime family".
Authorities believe the younger Utai is overseas.
Police have set up a task force to crack down on the escalating gang violence, furnishing it with more than 100 investigators.
Matt Utai starred in the 2004 NRL grand final, scoring two tries as his Bulldogs knocked off the Sydney Roosters.
His former club said it was deeply shocked and saddened to learn of the shooting.
The New Zealand and Samoa international played 167 NRL games, joining the Wests Tigers in 2011 and spending three seasons with the club.
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