Now he is taking on one of his biggest roles. The former All White has been appointed the Dunedin venue general manager for the Fifa Under-20 World Cup, taking over from Aaron Joy.
Joy was injured in a car accident in February at East Taieri, when he was returning from the airport after dropping off some tournament officials.
Following a few weeks soldiering on, doctors have advised him that to improve his health he must cut back on his workload.
So Joy has cut back his hours and McGarry has stepped into his shoes.
McGarry said it was a job of 100 different tasks and he was heading to Auckland later this week to get up to speed with senior tournament organisers.
However, he was thrilled to be involved in the competition, the biggest thing to hit the sport in this country.
He said Dunedin had the best group, with the best teams, in the best stadium, and had some great football to look forward to.
The first games are just weeks away, on May 30. Dunedin's first match on May 31.
''It is going to be great. Aaron and his staff have done a great job already and have plans well in place,'' he said.
''I've had a meeting with stadium staff and they are really supportive of the event. We're probably looking at a staff of upwards of 20 people when the event is here and about 250 volunteers which we have got.
''Now is the time for supporters to get in behind the event. And not just football people. We need everyone from Timaru to Invercargill and inland to the likes of Queenstown to get in and support this.''
Dunedin hosts Mali, Mexico, Uruguay, and Serbia and there will also be a match between Colombia and Portugal.
There will also be a knock-out game played. All up, seven games will be played in Dunedin.
McGarry has been seconded to the position and will take time off from his job at Otago Boys' High School.
McGarry (49) said people should not underestimate the standard of football to be expected.
''The captain of Uruguay [Jose Gimenez] plays for Atletico Madrid and starts for them and they are in the final eight of the Champions League. There are going to be lots of great players on show. They might not be household names yet but they will be soon.''
He said the Cricket World Cup had done the football code and the tournament a favour.
''Now the Cricket World Cup is out of the way and has been so successful that should help us. People have had a taste of tournament play and what it means. Now we can lift the profile of this tournament.''
He would be spreading the word around clubs, schools and other organisations in the coming weeks.
The stadium, which will be renamed Otago Stadium for the tournament, will host three double-headers, and McGarry confirmed one ticket for the day will get access to the two matches on that day. The first games are on May 31.
Ticket sales were going all right, McGarry said, but Dunedin people were traditionally slow out of the blocks and he pushed for people to get out and buy tickets now.
The tickets were very reasonably priced, he said.