This was called off, the World Ploughing Organisation's governing board saying the attack on Ukraine was "atrocious conduct", a clear violation and breach of international law and in contradiction to its slogan: Let peace cultivate the soil.
Fortunately, Ireland stepped in at the last minute after Russia was stripped of the hosting rights and the contest will be held in Ratheniska, County Laois, starting on September 21.
From a purely competitive perspective, the champion Timaru ploughman is saddened by the lost opportunity, but when one door closes, another opens.
Mehrtens couldn't be happier that he will return to Ireland for a third time to chase the elusive world reversible ploughing title and rekindle friendships.
"The Irish are very passionate plough people. When you go to the world ploughing in Ireland there will be 300,000 people there - it's huge. I've been pretty fortunate that I've ploughed in Ireland the last two times in 1996 and 2006 and it's just a sea of people."
He admits he didn't plough well by his own standards at either event, so hopefully, it will be a case of third time lucky.
Only three Kiwis have won the world conventional title, with the reversible yet to be claimed.
Mehrtens has come closest, placing second in Kenya in 2017, and the ambition to one day top the podium remains strong.
"It's there for everybody and the best man will win on the day. That's the way it goes.
"To be honest, in Kenya I knew I did pretty good the first day but didn't think it would be that good ... I was sitting at the prizegiving like everybody else because no one knew the second-day points, which are added together to find the winner.
"They're rattling off all these places and the Frenchman got third and I wasn't expecting anything, so when they called out second for New Zealand I thought ... that's me. I was quite shocked and it was a real buzz."
The 60-something ploughman has contested about 13 world championships since going to the Netherlands in 1989 with several top-10 performances. On the domestic front, he has made about 45 national finals.
He started off in conventional ploughing until rule changes for the world event insisted that each country had to send a reversible and conventional ploughman.
"Seeing I'd been away a few times in the conventional they said to me 'we want you to plough reversible'.
"I wasn't very keen on it for a start, in fact, I hated it because I didn't know anything about it, but now I wouldn't go back - I love it."
Competing in the reversible for the first time in Canada was an eye-opener and he watched the other competitors "like a hawk" to come to grips with ploughing on an angle.
The huge challenge and technicality of working with two ploughs appealed to him. One is on top of the other and the driver has to match them together - a bit like a "husband and wife team".
If one mould board or part of the plough is altered then the others have to be adjusted or it throws everything out.
The competitor ploughs on an angle to their neighbouring competitor, with every furrow lined up as a single. At the end of each furrow, the plough is lifted and the turning tractor lined up for the next sweep.
Even having the tyre pressure down on one side can put the furrow line out and a small compressor is always carried.
With no room for error, an angle grinder has been used to match the front tyre shape to the rear so it doesn't brush the finished furrows.
To get good at reversible ploughing requires huge commitment, dedication and many miles passing under tractor wheels, he says.
He probably does more ploughing matches than anyone else, once competing in every event in the South Island, from Blenheim to Tuatapere.
This has given him a solid grasp of the many soils encountered on competition days when he hones his skills under pressure.
Regrettably, he won't be able to ship his tractor and plough unit to Ireland, because of the short notice.
This goes against the normal practice of Kiwi qualifiers, who usually team up to squeeze both tractors and ploughs into a 40-foot (12.2m) container.
Rising shipping costs, container unavailability and the risk of them getting stuck in some port have put a dampener on that.
In 2017, he took the gamble and shipped the rig to the Kenya world championships and it paid off.
"Everyone said I was mad, you will never see it again. It was the best thing I ever did.
"It's a huge advantage having your own gear. Some of the countries over there - I won't name them - thought they were being clever and they weren't prepared to take the gear and the risk. There was a risk, but I look back on it now with fond memories because I got second over there.
"We went over there and undid the container doors and went practising for the first two to three weeks.
"And then the clever countries turned up with borrowed tractors and even though they had the identical tractor at home, the linkages were different, the hydraulic hoses wouldn't fit and the hair was being pulled out and they spent days and days getting organised.
"What were we doing? We were practising, so that's the difference."
Without his trusty Ford and personal plough, he has had to rely on others for help to compete in Ireland.
This is where the close relationship between Irish and Kiwi competitors has come to play.
In 2010, when the world event was held in Methven, in Mid Canterbury, an Irishman rang him up and asked if he could borrow his gear. Without a second thought, he agreed.
"I said 'yes you can' and never hesitated. Little did I know that many years later that was going to come back and help me because I rang them up just a few weeks ago to find me a tractor and the next night they found me an identical tractor and plough ... It just goes to show you that you have to give to receive."
The Irishman was Thomas Cochrane, a world reversible champion who got second at the Methven event.
They have become close friends, freely exchanging pointers even though they are rivals.
While it will not be his own rig, he is heartened that Cochrane and others have achieved at a high level on borrowed gear.
As a diehard Ford fan, it doesn't hurt that he will also be sitting on a beloved blue tractor.
"If it's not blue leave it in the shed. I'm a Ford man and have been all my life. I did play with a Fergie a couple of times and when I went to Austria I couldn't get a Ford - I had to use a Steyr. I like Fords - I'm biased."
The 1998 Ford 7740 has been his go-to tractor for competitive ploughing since it was found in a dealer's yard "scruffy and unloved" after a tough working life in Te Anau.
Weeks were spent getting it back to its former glory and it is in mint condition now, so much so that he has turned down offers to buy the machine, despite 14,500 hours on the clock.
Tractor age is not a factor, he says, it is about who is sitting in the seat.
Strictly speaking, the four-wheel-drive 100-horsepower tractor is overpowered for the 800kg plough unit but has enough grunt to always be in control of it, rather than the other way around.
Joining him in Ireland will be Blenheim's Ian Woolley, who qualified last year as New Zealand's conventional representative.
The pair qualified again to go to next year's world event.
They led the field last month at the national championships in Seddon, in Marlborough, Mehrtens amassing a total of 391.5 points and Woolley 404.5 points.
Ireland was due to hold this event so a new host needs to be found after it replaced Russia.
Mehrtens says there's still doubt whether it will be held.
"We don't know where we are going next year. In fact, at this stage, we're going nowhere because no country has stepped up because of all this Covid stuff.
"It wasn't long ago they had 10 to 15 countries lined up to have a match so that's just the way things go. Who knows where it will be, if at all?"
So the focus for the pair is on Ireland.
Coming with him on his flight will be his plastic mould boards.
He was the first to bring in the shaped blade made of Teflon that turns the furrow over - after seeing them at a world event in France in 1999.
Those who initially looked askance at them became believers when they saw the nice shiny furrows he produced.
Today, they have mostly replaced steel on the domestic and - with the exception of the Irish - on the world stage.
The former cropping and sheep farmer runs his own trucking business so the Ford and its accoutrements are only used in the competitive arena, or for practice runs on the many farms he services.
After leaving the family farm, he began carting grain in 1990 with one truck.
Today, the family firm continues to transport grain and spreads lime and other fertiliser on mainly local arable farms.
"I have a policy I won't pinch work off anybody, so I won't go to your place and say I want to do your job and they have to come to me - that's how it works.
"At the same time as we started the local carriers in our area got bought out and got sold to unknown people so it was quite good timing because a lot of people don't like change or go and jump ship.
"So at the same time this outfit that was doing all the work got sold to a new buyer and it was an ideal opportunity for them to come to us and I've never looked back.
"I've kept it small, I've kept it simple and it's a family-owned business. We only have three trucks, but we service quite a few big farmers now."
His wife Raewyn remains his greatest supporter and he is immensely proud that two of their four children are involved in the business.
Daughter Katrina drives trucks when she is not working as a part-time dance instructor and the eldest daughter, Mirinda, does all the accounts remotely from a North Island farm.
There are also hopes the other two, Andrew and Hanna, might join the business in the future.
Despite such a time-consuming hobby, Mehrtens still finds time to be involved with classic trucks.
On display at a museum on the north side of Timaru are six of his own vehicles, including an English-made 1929 wooden cab, Dennis, that used to be a milk truck in Waimate and was found on a Temuka farm.
His 1970s and 1980s Bedfords are his favourites, but the Ford-blue colour is never far away with two of them - and all his working trucks - painted the colour.
"I've always had blue tractors and that's the way it's going to stay. My grandkids will be driving blue."
