Kirwan said he had a good idea of the starting XV for the Highlanders match but would finalise the team at a selection meeting this morning.
Marshall has focused on learning the playmaker's craft after arriving from the NRL and Wests Tigers, but his short spell at the back during the Chiefs' 43-19 victory at the Rotorua International Stadium last Friday, which he enjoyed immensely according to Kirwan, suggests wearing the No15 jersey is a distinct possibility later in the season. He again had a quiet game at No10 but his ability to cover fullback means he could also provide a valuable bench role.
Charles Piutau is likely to start at fullback against the Highlanders.
"He came off the field and was really buoyant about playing 15 minutes there because it's a different game back there for him," Kirwan said of Marshall.
There were few other reasons for Kirwan to be cheerful as the Chiefs ran in six tries to three in Rotorua. He cut a frustrated figure afterwards, saying "we've got a little bit of work to do", but yesterday was taking a more philosophical view.
"We improved on areas from the week before - our ruck was much better and our breakdown went well, we're just not protecting the ball. Most of their tries came from our turnovers. I think they scored five tries from turnovers and you can't afford to do that to anyone let alone the defending champions.
"It would have been nice to put a performance together - we didn't do that in pre-season - but I'm not concerned at all."
Kirwan appears determined to put the lessons from last season, when the Blues faded after an excellent start, to good use. He will rest front-rowers Tony Woodcock and Keven Mealamu this weekend and underlined his philosophy of building and maintaining momentum throughout the season.
Midfielder Ma'a Nonu hopes to return from ankle surgery for the Blues' second game of the season against the Crusaders at Eden Park, with loose forward Jerome Kaino expected back from Japan at the end of the month.
"I think it's important to finish better," Kirwan said, when asked how important a good start was.
"Every coach wants to start with a win - if you do that you put points in the bank and that's so important. But I think consistency across the whole competition is more important.
"As you saw last year, we started with a hiss and a roar but then in the grind we lost our way a wee bit. We need to address that.
"What did the Chiefs do? They started well, got a couple of wins early and then in the grind they won a couple of really hard-fought games they needed to win."
Countdown to kick-off
Today our team of rugby writers begin their countdown to the New Zealand franchises' entry into Super rugby, beginning on Friday night with a mouth-watering clash between the defending champion Chiefs and the competition's most successful side, the Crusaders.
Today the focus is squarely on the Highlanders.
Highlanders out for redemption
Rising hard man ready to hook into role at top level of the game
Southerners must regain the respect of supporters
Tomorrow it will be the Crusaders, moving north up the country until we shine the spotlight on the Blues in Super Sport on Friday.
On these pages, too, you will find mini-profiles of the Lions and Rebels, two franchises expected to struggle this year, although the newly-promoted South Africans kicked their season off with an unexpected win yesterday against the Cheetahs.
Sit back and enjoy the coverage.
