Such performances are becoming common. Boult scythed through 10 West Indies wickets for 80 runs in Wellington last summer and has taken a wicket in all his tests except the recent outing against Pakistan in Abu Dhabi.
The signs were promising with his first wicket on debut in the defeat of Australia in Hobart, when Mike Hussey misjudged one nipping away. The list of victims now includes Chris Gayle, Jacques Kallis and Alastair Cook (all multiple times), and Sachin Tendulkar, Mahela Jayawardene and Hashim Amla (once each).
Boult's ability to generate swing has him on the World Cup radar. His skills are useful with a new white ball at each end. Still, having played just 10 one-day internationals for 10 wickets at 39.60 with an economy rate of 5.04 means there's much to prove.
"I look at my ODI career, and even my List A and T20 career, and it makes pretty light reading," Boult says. "I've gained confidence at ND playing in the HRV Cup and having a stint in the Champions League this year when I played opposition renowned for taking down bowlers. I had to sink or swim."
The consensus among the selectors is Boult 'swum'.
The 25-year-old's work ethic always shone, even as a third-former at his beloved Otumoetai Cadets.
Ben Williams runs a cricket academy at Tauranga and first met an 11-year-old Boult as a fledgling teenage coach. He remembers a sense of dedication and a determination to rebound from disappointment.
"As a 14 or 15-year-old, he missed selection for a Bay of Plenty development side," Williams remembers. "He was dark about that and, from then, it's been a case of developing a sheer full-blooded belief in himself. It's been inspiring to see him pursuing his dream.
"His commitment through his teens was sensational. I don't think I've seen a youngster trying to perfect his wrist position and seam presentation as much. It's all paid off.
"He's got a tight circle of people around him, like his family including his brother [and fellow first-class cricketer] Jono. Some guys tend to search for the right ingredients by tapping a lot of shoulders. Trent trusts himself to make the right decisions under pressure through self-belief."
Boult's never forgotten Williams' backing. On Thursday, he bowled at the academy, despite having already done a gym session and went for a run up Mt Maunganui later in the afternoon.
"Any chance he gets to give back, he's willing," Williams says. "He always comes to camps and clinics to speak and get involved with the kids."
Speak to anyone about Boult and 'fitness' and 'loyalty' are terms dropped into conversation. He even played for his club yesterday, taking 5-24.
"Otumoetai College wasn't the strongest for cricket so I joined the [Cadets] club in third form," Boult says. "I've got a lot of good mates there. It's what I've grown up doing. I love going back, playing club cricket on Saturday and socialising afterwards."
With a World Cup on the horizon, Boult knows the socialising can't be too excessive, even in the wake of a three-test tour. He's led by example as the player several acknowledge as the fittest in the team.
The maintenance of his fitness is partly driven by a back stress fracture in 2009. Earlier in the summer, he'd been a shock selection in the New Zealand squad to play Australia in the Chappell-Hadlee series, inspiring headlines like 'Boult-er'.
He played a Prime Minister's XI warm-up match in Canberra and toiled in the nets but believes, in hindsight, his failure to play an ODI and the subsequent injury that summer were blessings.
"I was severely inexperienced, having played a handful of games for ND and about to play the best team in the world. My head was spinning.
"[The injury] was mainly a workload thing. Too many overs in too short a time. Something gave way. It made me appreciate fitness more and how resilient you have to be.
"I like to keep it as relevant to cricket as possible, so mainly speed stuff on the track and grass. I also love my golf and surfing but I'm not a huge fan of the bike or rowing machine. You don't use them when you run in to bowl."
Boult also says he has got to monitor his intensity levels during matches and tours.
"I used to come in and bowl as fast as I could but, over the years, I've learned there are times you have to bowl within yourself. I always talk about Dale Steyn 'sniffing the moment' to take the initiative in a game.
"A lot of people talk about 'the zone' but I prefer not to overthink it. At the Basin [during the 10-for] against the West Indies, I was just running in and letting it go hassle-free. Simple is the best recipe. Making sure I had the right wrist position was as complex as it got."
Boult's rise hasn't gone unnoticed by the country's pre-eminent left-armer, Richard Collinge. The 68-year-old took 116 wickets for New Zealand in the 1960 and '70s at 29.25 and played in the maiden test victories over Australia and England. He lives in Sydney but has kept an eye on Boult's emergence.
"I saw him live at the Basin during our 1973 England tour reunion last year. He's got a smooth run-up and action, and moves the ball at a lively pace," Collinge says.
"Take the Younis Khan dismissal recently [in Sharjah]. That was a peach of a ball. I know the Hobart victory was his debut but I would love to see him in action when New Zealand next play Australia [next summer] because I believe they're vulnerable against the moving ball."
If all goes to plan for Boult and New Zealand, Collinge might get his wish this summer on March 29 at the Melbourne Cricket Ground in the World Cup final.
NZ's highest wicket-taking left-arm pace bowlers
Richard Collinge
Wickets:116
Tests: 35
Average: 29.25
Trent Boult
Wickets: 99
Tests: 28
Average: 27.85
James Franklin
Wickets: 82
Tests: 31
Average:33.97
Neil Wagner
Wickets: 55
Tests: 15
Average: 33.89
Shayne O'Connor
Wickets: 53
Tests: 19
Average: 32.52
Gary Troup
Wickets: 39
Tests: 15
Average: 37.28
Murphy Su'a
Wickets: 36
Tests: 13
Average: 38.25
