What is harder to ignore is when, rather than if, the 35-year-old makes way for the heir apparent.
The test calendar helps frame the case for and against the pair with New Zealand meeting Ireland (one away), England (three away), India (two home) and Australia (four away) across the next 13 months.
In fairness to both, their glove work looks sound.
Blundell has the advantage of experience, having played 37 of his 44 tests in the role. He can point to an institutional knowledge and muscle memory built from working with bowlers and captains since 2017, which can provide intangible benefits when the pressure mounts.
Hay brings youth and a literal spring in his step, having leapt in the lineout as a lock back at first XV level with Christchurch Boys’ High School. He was tidy behind the stumps in earning black cap No 292 at the Wellington test, nabbing three catches and orchestrating a run out.
Batting is where the case will effectively be decided.
Blundell’s form has dipped in recent years.
He averaged 58.54 from 13 innings in 2022 and 36.08 from 13 opportunities in 2023, contrasted against 23.30 from 22 knocks last year and 11.66 from four digs this year. The latter is a small sample size, but the trend is concerning.
Conversely, in relation to the upcoming itinerary and compared to a career mean of 33.43, Blundell averages 69.50 away against England, 39 at home to India and 43 away against Australia. How much weight do those numbers hold?
Hay’s case continues to strengthen, boasting a first-class average of 48.90 from 30 first-class matches.
He played the percentages well to harvest 61 on debut from number six, keeping the ball down and showing a willingness to attack anything loose.
A series of authoritative strokes between backward point and deep cover showed intent, as well as a share of forceful pulls through mid-wicket.
Like Blundell, Hay also fits the mould of someone prepared to work with whatever edict the team issues. That attitude should see him make a seamless transition.
Such an ascendancy means any margin for complacency has been erased.