Lefthander Worker hasn't had many chances but is familiar with walking out behind the fielding side; Phillips is well versed in it too but is finding his feet on the big stage.
Munro has never opened in an international. His career has been built on assertive middle order batting.
His overall average is 25.26 and he's had his share of misses in between some bruising contributions.
Now however, Munro is facing the prospect of a chance to fulfil a surprise role in the national side. And remember, there's a long summer ahead and a pile of ODIs, and T20s to follow. Translation: big chance looming for the 30-year-old lefthander.
Munro won't die wondering. He has never known a half-volley he hasn't wanted to smear out of the ground.
Sometimes his judgment has been lacking, but there's no question he can be immensely damaging.
Think back to his 14-ball 50 against Sri Lanka at Eden Park in a T20 at the start of last year, still the second fastest in balls faced in T20 internationals, behind only the 12 balls of Yuvraj Singh against England in 2007; or more recently his 101 off 54 deliveries against Bangladesh at Mt Maunganui at the start of this year.
Balance that with his ugly first-ball swipe at South African quick Chris Morris at Eden Park last February which scattered his stumps. New Zealand disappeared down the plughole for 107 in 14.5 overs.
There were many who wondered if that might be Munro's lot and off he'd head to the various T20 circuses which would seem tailormade for his crowd-pleasing qualities.
Instead he has an opportunity. A couple of twenties in the two warmup games in Mumbai have got him into the swing of the tour.
"Colin and Martin have started nicely for us," coach Mike Hesson said.
Worker had a niggling hamstring strain which won't help his selection chances tonight, so Munro it is. But Hesson said the idea was not to use him in a pinch-hitting role. He wants more out of the player than that.
"The ability to go out and play instinctively is important. Colin is definitely a boundary hitter, but both Colin and George are busy players."
With Tom Latham pencilled in for an important middle-order role, and taking the wicketkeeping gloves, the opening is there, so to speak, for Munro.
The question, which should be answered in the next few days, is whether he's able to grasp it.