It's likely the largest practice Investors Group Field will ever see.

"One Heart" is a massive church service that will be held there Sunday at noon.

Church of the Rock Pastor Mark Hughes, one of the organizers, said it will be a dry run for everyone associated with the new home of the Winnipeg Blue Bombers.

"Investors Group Field people are really trying to go through the entire motions of what it would be to run a regular stadium event with the parking, with the tickets, with the bussing, (and) the park and ride," he said.

"We're trying to do everything we can to help be a true test run for them."

The football club unveiled its parking plans in April.

The multi-denomination church service is expected to attract 25 thousand people.

Hughes said the congregations from the 91 churches involved have all been told to car pool.

"We've told people a minimum of four people per car," he said

"That alone will cover a lot of it. I think people are going to respect that and understand ...You know, that's just not good insight to just show up with one person to a vehicle."

Hughes said there are also a number of shuttles at nearby churches, including one at the Church of the Rock on Buffalo Place, just off McGillivray Boulevard.

The event gets underway at noon.