Lawrence and Steve Walsh, who refereed quarter-finals, have been ruled out of further matches because of their nationality conflicts and Lawrence's untidy work in his quarter-final match.
Hansen felt the All Blacks' work in the tackled ball area was a bit slow for their plans against the Pumas.
They wanted to play with quick possession but that inability reflected the strong work of the Pumas' defensive systems. "We have got to be more effective, not commit more people to the breakdown," Hansen said.
Hansen coached Wales in 2002 and at the 2003 World Cup against New Zealand before linking up with Graham Henry and Wayne Smith on the All Black coaching staff the following year.
Asked what it was like to coach against the All Blacks, as Wallaby supremo and former All Black assistant Robbie Deans does, Hansen likened it to playing against your brother.
"It becomes a little personal, I guess, and you want to be successful and I am sure that is how Robbie is feeling," he said.
The first few times were a little weird but Deans would be well used to that arrangement after the sides had clashed 14 times - for three Wallabies triumphs - since he began work in Australia in 2008.
Hansen had coached Wales and then the All Blacks in the same year and that provoked equal dollops of love and loathing from Welsh supporters.
He was unconcerned about captain Richie McCaw's injury niggles. That was a standard situation for all test loose forwards and the World Cup was an event which tested those who were the strongest and lasted the longest.
McCaw was sore but would captain the All Blacks in this transtasman duel. Adam Thomson failed a fitness test yesterday and his place on the bench is likely to go to Victor Vito when the team is announced today.