Next thing the Horned Frogs coach knew, four high school swimmers were coming through the door, needing to use the bathroom.
''How about that?'' Johnson said. ''So I had to leave. I thought they'd be in there and get their business done and be right out. But I had to knock on the door for about 10 minutes.''
As for how much of an inconvenience a high school facility with a natatorium attached has been for the likes of No. 8 Kansas and Texas, well, not as much as some might think. Sure, the Wilkerson-Greines Activity Center is fairly cozy and has tall walls near the court adorned with Fort Worth school logos such as the Polytechnic Parrots.
But chairback seats and concourses have offered a surprising feel for players, coaches and fans who might have expected the one-time experience to be something out of ''Hoosiers.'' In short, ''arena'' might be a better word than ''gym.''
''I thought for the sacrifices they've had to make probably this year, it certainly was better than what I thought it would be coming down here,'' said Jayhawks coach Bill Self, whose team hung on for a 64-61 win last month. ''It's a nice facility, without question.''
The Horned Frogs are spending one season about 10 miles southeast of Daniel-Meyer Coliseum while the 54-year-old facility undergoes a $45 million facelift. The facade will match that of TCU's recently renovated football home, Amon Carter Stadium, and have more courtside seats and wider concourses.
In the meantime, senior Kyan Anderson and his teammates hop on a shuttle bus for the roughly 15-minute drive to home games at a site that also includes one of the Fort Worth school district's football stadiums and plenty of free parking, one of the reasons along with scheduling issues that the site was chosen over the Fort Worth Convention Center downtown.
The roughly 5,000 seats are orange - but at least they're not Longhorn burnt orange. A little brighter. And TCU put up purple banners and other signage to try to make it feel more like home. High school officials told TCU not to take them down between games because their players thought it was cool.
''It's been fun,'' said Anderson, who played high school games for nearby North Crowley on what became his temporary home court. ''I've gotten that question a lot, and it really doesn't matter where you play. It hasn't affected anything with me or the team.''
TCU split the bill with the school district for a new court and had to install 35-second shot clocks above each basket. Scoreboard weren't a problem, though. The facility already had a four-sided board hanging over the court, and two large ones just below the roof at each end of the floor.
Since they were redoing the floor, TCU officials decided to put most of the wiring under the court. Equipping the facility for live television and better Internet access was a key part of the upgrade as well, along with improved lighting.
The shiny floor reads ''Robert Hughes Court'' with an accompanying basketball in two places along each sideline. Hughes was the Dunbar High School coach who retired 10 years ago and is still the national leader for boys high school victories with 1,333.
While the building is big enough for shooting sightlines to feel like an arena, there are the neon signs on the walls of all four corners that read ''open.'' When they're on - and they all have been for the TCU games - that means the concession stand on the other side of wall is taking customers.
''Felt like a high school game kinda with the gym, just the atmosphere, everything,'' Kansas guard Frank Mason III. ''It kinda like made me think of old high school days and games and things like that.''
The temporary home hasn't changed TCU's fortunes much in the Big 12. After starting 13-0 against a mostly inferior schedule - and many of those games in their temporary home - the Horned Frogs are 1-10 in conference, putting them at 3-44 since joining the league in 2012.
While staying competitive, the Frogs have lost all five home conference games. That's not exactly ''defending the Wilk,'' the phrase that senior associate athletic director Jack Hesselbrock says the players came up with for a light-hearted approach to missing their real home floor.
''Obviously I would have liked to play in there, especially being here so long and playing in the DMC and being able to get that new renovation,'' Anderson said. ''At the same time, after this is another chapter.''