U.S. Bank Stadium’s end zones have gone blue, red, white and green for the New England Patriots and the Philadelphia Eagles.

NFL executives brought reporters onto the field Tuesday for a tightly controlled sneak peek at the transformation of the roughly 18-month-old building that will play host to the 52nd Super Bowl on Feb. 4.

Eric Finkelstein, senior director of events for the NFL, and Ed Mangan, the NFL’s field director for the Super Bowl, said everything’s on schedule despite losing two weeks of renovation time because the Vikings hosted a divisional playoff game a week ago.

“There’s a lot to be done, but it’s encouraging to see the field painted,” Finkelstein said. “Even with the weather, we feel pretty confident.”

The western end zone, closest to the big glassy facade with the five pivoting doors, carries the Patriots name. The eastern end is deep green, black and white for the Eagles. Mangan said two Vince Lombardi trophies will also be embedded in the turf on either 25-yard line. Only one team will leave the building with the real trophy.

The most obtrusive element on the field Tuesday was massive metal rigging at midfield that occupied the full width and at least a third of the length of the field.

The rigging carries supplemental lighting for Justin Timberlake’s halftime show and will be hoisted toward the stadium’s ceiling. Finkelstein didn’t know much else. “They usually keep it very close to the vest, even from me,” he said.

Halftime show rehearsals are, for now, happening off-site.

Many of the visible preparations involved eliminating all Vikings branding inside the building to make it neutral. Evidence of the Vikings remained, although many areas had been covered with the blue-purple hues of the NFL’s Super Bowl LII branding.

Construction on the main concourses above the eastern and western end zones was visible from the field. Broadcast booths with field-facing windows had been installed along a rail where fans can usually stand to watch the games.

Auxiliary press box space is going in to accommodate thousands of credentialed journalists. The stadium’s regular press box can accommodate only 250.

While the changes didn’t appear too dramatic, Finkelstein said, “There are many, many more behind the scenes that you’ll never know about.”

Those include adjustments to locker rooms and expanded interview areas in the bowels of the building.

The air carried the sawing and pounding sounds of work being done. The building was abuzz with groups of busy people coming and going.

Outside the stadium, massive white tents have sprouted on surface parking lots often used for tailgating during Vikings games. Those buildings are all part of the game behind the game, the preparation and storage areas that are necessary for the Super Bowl production.

Finkelstein pointed out that the footprint of the event is much bigger than a usual Vikings game because of security needs. The Super Bowl is a Level I National Security Event that brings in federal security agents and support.

All along, the NFL has said the building presents challenges because of its tight urban setting.

Mangan, who also works as the head groundskeeper for the Major League Baseball’s Atlanta Braves, liked what he saw inside, describing the space as “wide open” and “gorgeous.”