With just one non-first-class match before the Lord's test, there is probably just one piece of Mike Hesson's jigsaw to be completed.
New Zealand's coach and tour selector Hesson said Mark Craig, who took a five-for in the win against Somerset, would "no doubt" play at Lord's and with Jimmy Neesham's injury paving the way for Corey Anderson to return to the test team, it is likely that Doug Bracewell will keep the third seamer's spot ahead of a third leftie seamer in Neil Wagner.
That just leaves the second opener's position alongside Tom Latham to fill.
Guptill's side strain could have given the inside track to incumbent Hamish Rutherford, but a double of 37 and 11 answered nothing.
Hesson was non-committal when assessing Guptill's chances of making a Lord's appearance.
"He is on track to play next week," he said. "All going well in the next few days we are hopeful that he will get a start in the next game."
If Guptill can't play against Worcestershire, then his selection for the first test will be based on his good form for Derbyshire that included his first first-class double-century, and the belief that his one-day form is transferable to tests.
Guptill's class and shotmaking has never been in question, but his ability to think his way around test-match attacks has been. In a spluttering 31-test career, the 28-year-old has shown a fondness for the weak attacks of Zimbabwe, Bangladesh and the West Indies, and a frailty against the rest.
Guptill has sought the help of Martin Crowe to remedy some of his problems, particularly his footwork on defence, and the public came to appreciate the results during the World Cup, where his stunning unbeaten 237 in the quarter-final against the West Indies was the high-water mark.
He took that form with him to Derby, scoring 290 runs in four innings at an average of 96.6. While the portents are good, james Anderson and Stuart Broad at a lively Lord's will present a far greater challenge than a Gloucestershire attack that had Kieran Noema-Barnett bowling first change at Bristol.
Even if Guptill is not available for New Zealand's final warm-up, you have to wonder how much weight can be put on the hit out.
The Worcestershire match has been robbed of significant meaning by having first-class status removed to allow New Zealand to play more than 11.
If it's a sign of the times it is a lamentable one. A tour to England used to be something for players to treasure. Now it is something to squeeze in between the IPL and the Ashes, with once-valued matches against the counties reduced to joke status. Sad face.