Hanks says the players realise they can't rest on their laurels with the league but also factors in their fragility as "human and we'll make mistakes".
He agrees complacency may have played a part on Monday when the mentors were away but believes it should not have.
"If it did then it certainly won't happen again."
Hanks says factors, such as referees' decisions and two trips to Wellington in three days, hadn't made it easy for them but they were punished for taking a defensive stance in a bid to pull a goal back.
He says for a team such as Upper Hutt, it's like a cup final and powerhouses can be found out if they are missing a few key players because they have targets on their backs.
Robertson, who returned home on Wednesday, had asked the senior players to conduct a review of what went wrong in the cup encounter.
The Blues have retained their top perch but the side's five-point gulf over second-placed Stop Out has been whittled down to just two points.
They host mid-table Miramar Rangers in a 2pm kick off at Bluewater Stadium, Park Island, in round 11 of the league tomorrow.
Hanks says it's about getting back in the zone rather than changing the way they play.