Call it the drive for five or the fix for six.
The demise of Jesse Ryder's World Cup chances and likelihood Brendon McCullum will open for New Zealand at one-day international cricket's showpiece means, with 83 days until the tournament starts, there's a situation vacant at No 5, or possibly No 6, in the order.
Originally finding a second opener to join Martin Guptill was the problem but, with all indications McCullum is keen to jump back up the order, the 'situation vacant' is now further down.
With Kane Williamson and Ross Taylor ensconced at Nos 3 and 4, Corey Anderson at either five or six in the order and an XI completed by Luke Ronchi, Daniel Vettori or Nathan McCullum and three pace bowlers, that leaves one hole.
Tom Latham and Jimmy Neesham and to a lesser degree BJ Watling look the obvious contenders with Dean Brownlie, Colin de Grandhomme and Colin Munro worth watching on the current New Zealand A tour.
Latham featured in the middle order against South Africa last month when he contributed 29 off 38 and 16 off 28, so has the inside running. He has also impressed with his test performances, and last week scored a second test century in just 12 innings with a classy 137 against Pakistan in Dubai.
Circumstances have changed a little since the South Africa series, when Neesham was used as an opening experiment in that series, which now appears less relevant if McCullum shifts.
Neesham's bowling capability could give him an advantage and he has the strongest batting strike rate of the leading contenders with 92 - Latham's is 73 and Watling 69.
Watling has, however, worked hard on that aspect of the abridged formats. He averaged 38.60 as skipper on the New Zealand A tour of England, with a strike rate of 137, when he was picked specifically to close out an innings from the middle order. He also conceded no byes and took 19 catches with the gloves, meaning he continues to challenge Ronchi.
Complicating matters is that someone will need to fill an opening gap against Pakistan. McCullum is expected to head home after the tests as part of a rotation phase with the likes of Tim Southee and Trent Boult. If that occurs, Williamson will lead the side with Taylor also staying for more white-ball cricket.
Brownlie might be a suitable opening stop-gap, given his stated intention to perform that role more in shorter forms. Anton Devcich could also lay a claim.
Form will play a big part but irrespective, there will be three or four tough calls when the eventual squad is named on January 8.
Possible World Cup squad: Brendon McCullum (c), Martin Guptill, Kane Williamson, Ross Taylor, Tom Latham, Jimmy Neesham, Corey Anderson, BJ Watling, Luke Ronchi, Daniel Vettori, Nathan McCullum, Tim Southee, Kyle Mills, Mitchell McClenaghan, Trent Boult.