After a stand-out college career at the University of Southern California, the 23-year-old Ellison was drafted by the Minnesota Vikings with the 128th overall pick in the annual dispersal of the country's best collegiate talent.
A career which began as a nuisance on the schoolgrounds, disrupting his classmates' rugby games with a predilection for the forward pass, has culminated in reaching the highest level of the game.
"I was surprised to [be drafted] at all," Ellison says. "I was kind of going into it not thinking I was going anywhere. To get picked up by the Vikings in the fourth round - to get picked up by the Vikings, period - was a big surprise."
It's probably just as surprising to most New Zealanders to know there will soon be a Kiwi in the NFL. For that they have to thank the trailblazer from these shores, Ellison's father Riki.
Riki Ellison was born in Christchurch and moved to the United States as a child, before going on to win two Super Bowls in a 10-year career with the San Francisco 49ers and Los Angeles Raiders.
He retained a strong connection to his New Zealand roots, and moved his young family to Christchurch once his professional football career drew to a close. That was where Rhett tried his hand at the local pastimes while always remaining drawn to the game of his father.
"I was a bit young," he says. "I tried to play rugby at lunch break and stuff like that, but I kept throwing the ball forward so that didn't last too long.
"I played a little cricket with my dad. We had a big field out the back of our house and I used to throw the ball around and try to play some cricket. But he had me doing football then, also."
Once he got his head around the forward pass rule, Ellison could have had a decent crack at rugby. He certainly had the pedigree.
The Ellisons, from Ngai Tahu, are descendants of Thomas Ellison, a member of the New Zealand natives team which toured Great Britain in 1888-89 and captain of New Zealand's first official rugby team in 1893.
Rugby may be in his blood but when Rhett Ellison moved back Stateside when he was eight, he had eyes for only one sport.
After following in his father's footsteps by gaining an early education at St Andrew's, Ellison also attended Riki's alma mater of USC. There, he became a co-captain of one of the best football programmes in the country - playing tight end and fullback in his four-year stint - and was recognised by having an annual leadership award renamed in his honour.
Despite finding college football like fulltime employment, Ellison also made time to earn a bachelor's degree in international affairs, but struggled to schedule any recent trips to visit family in Auckland and Christchurch.
"The last time I was there was my junior year in high school when I went out for a couple weeks in the summer," he says. "Once I got to USC, football's pretty much a year-round job so I didn't have a lot of spare time."
A lack of spare time has proved more than worth it now he has reached the ultimate goal. Players drafted in the back end of the fourth round last year were signed to four-year contracts in the region of US$600,000 a year, but Ellison wasn't attracted solely by the dollar signs.
"It's just like a dream come true. It's been a lot of fun to have my dad, who's done it, to help walk me through the whole process. I couldn't be luckier to have a dad who's played in the NFL.
"Just to get to play in the NFL is very amazing."
Ellison has yet to discuss with his new coaches his immediate playing role in Minnesota, with various fan sites projecting him as a special-teamer (kick-offs, punts, field goals), starting fullback or back-up tight end, but he says he will do whatever the team needs.
Minnesota finished last season with a franchise-worst record of 3-13 but Ellison hoped to recruit a few fans from his ancestral homeland - although they'd have to come to terms with the Vikings' particularly garish uniforms.
"If they can handle purple - it's not all black or anything. That purple's kind of hard to get used to."
