United coach Adrian Heath sat his team down for a video session ahead of its match Wednesday against the Colorado Rapids, highlighting various players sprinting down the field.

"People running 60 yards just to get back goal-side of the ball," Heath said in a team-provided interview. "And in these conditions, that's not easy to do."

Those conditions include the Orlando heat, even at 9:30 p.m. kickoffs such as Wednesday's. And the four-month layoff between the start of the MLS season and the MLS is Back Tournament.

Combined with playing in a bubble amid a global pandemic, it certainly makes for a tough environment.

But United's defense hasn't crumbled under all that.

In fact, Heath called the collective team defense, from the back four to the strikers, what he's been most satisfied with in his team's two tournament games.

The Loons defeated Sporting Kansas City 2-1 before managing a scoreless draw against Real Salt Lake.

They appear likely to move on to the knockout rounds after the final Group D match against points-less Colorado.

Heath described the defense as having "a great appetite for the hard work," with players unafraid to make the extra effort.

The Loons have done that without some of their usual leaders, including center back Ike Opara, out with a pre-existing condition.

Others have stepped up, including Jose Aja taking Opara's spot. Left back Chase Gasper praised Aja's contributions in a team-provided interview, calling him a "fantastic, no-nonsense defender.

"He has broken a lot of plays, stopped a lot of dangerous counterattacks from the other team. And I think he's just been a huge help to our team."

Heath also praised center back Michael Boxall, who filled in as captain for midfielder Ozzie Alonso in the first game.

Goalkeeper Tyler Miller has allowed only one goal, a moment he chalks up to shaking off his own rust when he over-read a pass he thought he could intercept.

But he's come to realize that everyone is a little out of practice — including the opposing strikers — and sometimes playing it easy is the best option.

United has been a part of some tight games already, with Miller facing only five shots on target in the past two matches. Heath said he expects another close game against Colorado.

With the Rapids needing a victory just to keep a wisp of hope for advancing, Miller is ready to expect anything.

"They're definitely going to be pushing for it," Miller said. " … The third-round games that I've seen from around the league, I've been seeing more goals coming. So I feel like as teams are getting kind of used to playing again in this type of environment, they're taking more chances, more risk, and it's leading to more goals."

That might be a welcome change of pace. Miller said it's far harder to play in a game with few scoring opportunities because there's no chance to establish a rhythm or temper the adrenaline, which makes every shot feel like life or death.

That may explain Miller's one allowed goal, though he feels he's steadily acclimated and improved since then.

The team as a whole seems to as well, developing defensive chemistry despite some missing pieces.

And as long as everyone keeps helping, Heath feels good about what his team can do in this tournament, which, after group play ends, continues with a knockout round of 16 from July 25-28.

"The days of just saying, 'Oh, it's up to you four in the back now to get on with it' have changed," Heath said.

" … It is a team game more so than ever, I feel now, in terms of defending and attacking, because it comes from all areas of the field.

"I've been really, really pleased with our mentality to defend the goal. And we're going to need that again [Wednesday]."