Much of the talk heading into the tournament was about the Real Madrid star's fitness and whether the FIFA Ballon d'Or holder would be able to shrug off the knee and thigh injuries that blighted the latter part of his club season.
The 29-year-old recovered in time to play in Portugal's tournament opener, but had little impact as Paulo Bento's men were hammered 4-0 by a clinical Germany side.
And Portugal now face the grim prospect of elimination from Group G should they lose to the USA and Germany avoid defeat versus Ghana on Saturday.
To steer clear of that scenario Portugal will need to produce a greatly improved display against a United States side who will be out to summon the spirit of 2002 and earn a place in the last 16.
Jurgen Klinsmann's team started their campaign in dramatic fashion as John Brooks' winner four minutes from time gave them a 2-1 success against Ghana on Monday.
That victory means that the USA can qualify for the next stage with a win, providing Ghana drop points again.
At the World Cup in Japan and South Korea 12 years ago, Germany claimed a 3-2 win over Portugal in their first pool game and went on to reach the quarter-finals.
However, this Portugal outfit represents a different proposition to the one the USA faced then, and Bento's side will be eyeing a response to their opening-game disappointment in Manaus
But Portugal will have to atone for their poor start without two of their best defenders.
Centre-back Pepe, who was shown a straight red following an altercation with Germany's hat-trick hero Thomas Muller, is suspended, while left-back Fabio Coentrao has been ruled out for the rest of the competition with a thigh injury.
The challenge for Bento will be fill the void left by the Real Madrid duo, with Valencia's Ricardo Costa and Benfica's Andre Almeida the favourites to come in after they replaced the pair in the second half of the meeting with Germany.
Meanwhile, Clint Dempsey seems likely to feature for the USA despite breaking his nose versus Ghana, but striker Jozy Altidore is a doubt with a strained hamstring.
