Ready to debunk fears that CFL football will run the stadium for soccer, he pointed to a faint outline just outside the official centre circle on the pitch.
"See the line we took out yesterday," he said. "No pressure-washing yet at all.
"We've been out experimenting at KIA (Toronto FC's KIA Training Centre) on how to do lines. So this was a garden hose. We came in yesterday and just got it wet. And the paint began to go away."
The line, Leiweke suggested, would be rendered invisible with use of a special high-pressure water machine.
"You don't even see them," he said of the football lines. "So we're like 'Guys, we're going to be fine.'
"If we do it (convert the stadium to football), TFC owns the schedule. We lock in the MLS schedule then we go back and lock in the Argos schedule. They've got 10 games. We'll figure out 10 weekends when we don't have a soccer game. We're fine."
And yet nothing quite inflames the blood of Toronto FC supporters as the suggestion that their lakefront venue will be tainted by football. A "No Argos @BMO" banner was prominently displayed at the stadium last week when Toronto hosted the Montreal Impact.
Many fans see opening up the soccer stadium to other sports as going counter to the MLS goal of soccer-specific stadiums. Others simply fear the CFL team will churn up the pitch.
Leiweke, who sees himself as a soccer guy, insists that the venue will be no different for soccer, Argos or not.
"For soccer it will look exactly like it looks today — there will be zero difference."
There is work to be done to accommodate the CFL.
Seats in the north stand will have to be reconfigured, with several retractable rows installed. The first seven or eight rows in the south stand will also have to be converted into retractable, removable seats to have space for the longer field.
Logos will be restricted to the endzones, said Leiweke, meaning they will not be visible during soccer games.
"We won't let them put logos on the turf," he said.
New, bigger dressing rooms will also have to be built to accommodate football.
The changes will be made as part of the second phase of renovations, to be completed by May 2016. They include putting on a canopy around three sides of the city-owned, MLSE-managed lakefront stadium as well as installing a new audio and lighting system.
A new hybrid grass system will also be installed, with natural grass growing around artificial roots to strengthen the turf. It's the same kind of system used by the Green Bay Packers, Denver Broncos and at Wembley Stadium.
With the canopy up, sunshine on the pitch will be limited. So MLSE has a $1.5-million heat machine on rollers that will be used to make up the difference.
"It's not the CFL that's the issue with the pitch, it's the winter," Leiweke said.
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