Thurston says Jennings had brain snap

Queensland halfback Johnathan Thurston said NSW centre Michael Jennings suffered a brain explosion during Wednesday night's State of Origin opener in Melbourne.

The 24-year-old centre, who is out of favour with his NRL side Penrith, left NSW vulnerable with 12 men in the first half after he was sin-binned for running into a brawl and throwing a wild punch which brushed Queensland winger Brent Tate.

It turned out to be the biggest or worst play on a night of controversy and drama.

"Jenko came in from a long way away with a swinging arm," Thurston said.

"I don't know what you'd call it, a brain explosion.

"Maybe it was the passion in the jersey and trying to stick up for his mate, I don't know."

Gallen had a crack at rookie Origin referee Matt Cecchin, quipping "this is your first Origin, it's different you know".

Queensland winger Darius Boyd dived across the line for the first of his two tries while Jennings was off the field, and his second on the stroke of halftime gave the Maroons a 12-4 lead.

Thurston said Gallen was in the referees' ears all night.

"Any decision that went against (them), Gal was in there complaining," said Thurston.

"He's a competitor and he plays with pride and passion in his jersey."

Asked if he was becoming the ultimate whinger, Thurston grinned and said: "you're trying to get me to say something, aren't you?"

Thurston said NSW were all over Queensland in the first 20 minutes and they were fortunate to get a few big decisions go their way.

"They'll get a lot out of their performance tonight," he said.

"They peppered us in the second half and they gave us a hiding in that first 20 minutes.