The Warriors returned from Franklin's Gardens with two losing bonus points courtesy of a remarkable four-try blast that brought them back from 37-3 adrift to just six points behind. But Hill admitted Worcester cannot afford such a dreadful start when they take on London Irish at Sixways tonight.
"We had a big inquest on Monday to find out why we went 37-3 down, because that is unacceptable," he said. "I think some of the players were in awe of the opposition at the start, and we can't afford for that to happen again."
He added: "London Irish will be full of confidence after getting their first win of the season last weekend, so we will have to make sure we start well.
"Our attacking game is working really well and we are producing good rugby, but we will have to concentrate on our defensive play against Irish.
"Irish will be a different prospect to Northampton as they will play a lot of rugby and move the ball around."
Rock-bottom Sale Sharks will arrive at Bath on Saturday after making unwanted club history less than a month into the new Premiership campaign.
Sale are reeling from four successive defeats - their worst start to a Premiership season - and they have collected just a solitary losing bonus point in the process. To compound matters, they are without injured internationals Dwayne Peel and Richie Gray this weekend.
Sale rugby director Bryan Redpath has made six changes from the side beaten at home by Premiership newcomers London Welsh last time out, including Danny Cipriani being relegated to bench duty.
It will also be Sale's first game since they parted company with forwards coach Steve Scott last weekend.
"There are opportunities for some of the younger boys in the club," Redpath said.
"It has been tough after last Friday's match and what followed at the weekend. We are desperate to get another game under our belt because some of the parts of last week's match were not what we expected."
Redpath hands a start to young flanker James Doyle, while scrum-half prospect Nathan Fowles is among the replacements, with Nick Macleod and Cillian Willis forging a new half-back combination.
"Last season, Sale went to Bath on the back of a disappointing home performance and won, later going on to complete a season's double," Redpath added.
"As I've said, last week was unacceptable, and hopefully we can show a big improvement."