The midfield duo's absence was very apparent against Panama on Sunday, showing just how important they are for the team's World Cup qualifying hopes

Part of qualifying for the World Cup in CONCACAF is proving you can survive, and even thrive, with different groups of players. And, in this new format that has required teams to battle through three games in a week, that fact has never been more apparent.

Through the first five games of their qualifying journey, the U.S. has proven they can survive without some key players. Brenden Aaronson has filled in admirably for Christian Pulisic and Gio Reyna.

Young center-backs like Miles Robinson are making life a bit easier even without John Brooks. Reggie Cannon hasn't even played in World Cup qualifiers, nor has Daryl Dike, a player that looked like the USMNT's striker of the future just a few months ago.

But, if Sunday's loss to Panama showed us anything, it's that the U.S. is still struggling to survive without its starting midfield with Tyler Adams, in particular, now as vital as ever as we near the midway point of the qualifying cycle.

Adams was relegated to the bench in Sunday's defeat while his midfield partner, Weston McKennie, was left back home in the U.S. to deal with a nagging injury. USMNT boss Gregg Berhalter explained that he felt Adams needed a rest, a chance to recover with a 45-minute limit meant to prepare him for Wednesday's home match against Costa Rica.

“With Tyler, we wanted him to play 45 minutes because of his load. And the other thing to keep in mind is prior to this camp, Tyler hasn't been playing regularly for [RB Leipzig],” said Berhalter.

“He had a little bit of injury, he was in and out of the lineup. So now to ask a player who hasn't had any load, or much lower than the last three weeks, to go play three 90s, I wasn't comfortable with it, and I'll take responsibility for that.”

We'd seen the USMNT without McKennie before, with the Juventus midfielder being kicked off the team last month for a rules violation.

But we hadn't really seen them without Adams aside from a tough first half against Honduras that was turned into a 4-1 win once the RB Leipzig midfielder was moved from right back to central midfield.

Well, we got a look at what an Adams and McKennie-less midfield looked like on Sunday and, by any measure, it was a mess.