“When you reach a semi-final, you need to suffer,” remarked Lionel Scaloni. Yet one might wonder if Argentina truly needed to endure quite so much. After being pushed into extra time by an injury-hit Switzerland, just as they were earlier by Cape Verde, and forced into a record-breaking comeback to defeat Egypt, the reigning champions’ progression through the knockout rounds has been marked by struggle.

Following the hard-fought victory over Switzerland in Kansas City, Scaloni repeatedly pointed to one key reason for the challenge—physicality. “Physically, they are a very strong team,” he said. “It was extremely difficult for us to win the duels. Switzerland are excellent on a physical level.”

Perhaps Argentina are not. They have shown resilience and stamina to score late goals—netting in the 79th, 83rd, 92nd, 92nd again, 111th, 112th, and 121st minutes in their last three matches—but physicality comes in many forms. Their most iconic player is known for his skill rather than his physical presence: now approaching his forties, he spends much of the game walking, though his technical brilliance remains unmatched.

Lionel Messi, indeed, runs very little these days. Yet his teammates may not make up for it with pace. According to FIFA data, Argentina rank only 10th for total sprints, behind three teams who have played one match fewer. Even more striking, they sit 48th out of 48 for average player movement speed at this World Cup. In that regard, Messi’s lack of running could be holding them back.

Individually, Messi ranks 580th for average speed; even Cristiano Ronaldo comes in at 501st, with some of those behind Messi being goalkeepers or central defenders whose roles demand less movement. This is not a criticism of Messi himself, but rather a reflection that his teammates are not compensating with the required high-energy running.

On Wednesday, Argentina’s opponents England will feature Jude Bellingham, who sits second in the World Cup for most sprints made. The first Argentinian on that list, Enzo Fernandez, is tied for 19th place. In FIFA’s chart for high-speed running, roughly 20 players rank ahead of anyone from Scaloni’s team.

Meanwhile, the two players who have covered the most ground in the tournament are Swiss midfielders Remo Freuler and Granit Xhaka. Alexis Mac Allister is the sole Argentinian in the top 20 for distance covered.

This could explain why Argentina struggled to make their numerical advantage count after Breel Embolo’s red card, despite having an extra man. It is worth noting that Switzerland had already played 120 minutes against Colombia in the previous round, and were down to 10 men against Argentina for over an hour including stoppage time. They only began to collapse in the final 10 minutes. Argentina’s next test comes against another European side, England, whose coach Thomas Tuchel has urged his players to display Premier League-level pace and power.

That could pose difficulties for Argentina. Both Cape Verde and Egypt exploited them on the counterattack; when Argentina open up play, they often find themselves exposed in one-on-one races they tend to lose.

To counter this, Scaloni introduced Leandro Paredes to provide more defensive cover during transitions. It was not entirely successful against Egypt, but it appeared an acknowledgment that even with Mac Allister, Fernandez, and Rodrigo De Paul, Argentina may lack enough solidity in midfield.

However, the strategy of clustering players around Messi leaves gaps elsewhere, particularly on the flanks. Cape Verde’s first goal came from their right flank and the second from the left. Similarly, Dan Ndoye’s equaliser for Switzerland, Egypt’s disallowed second goal, and the subsequent one that stood all exploited Argentina’s narrow shape. Their full-backs often lack protection—a vulnerability England could target, especially since Tuchel prefers his wingers to maintain width and use their pace.

England, however, have physical issues of their own. Declan Rice has been hampered by a hamstring injury followed by illness. Bukayo Saka and Reece James have dealt with Achilles and hamstring problems respectively, while John Stones continues to struggle with fitness concerns. Like Argentina, England also endured 120 minutes in their quarter-final.

This semi-final looks set to feature two teams that have shown resilience under strain—creaking, perhaps, but not breaking. Argentina’s experience and mental fortitude could once again carry them through. Yet, if they seem to lack mileage in this World Cup, they may already have too many miles on their legs overall. Scaloni’s lineup against Switzerland was the oldest to feature in a World Cup quarter-final since Brazil’s 1962 team—a side that, as history notes, went on to retain the trophy.

Scaloni will now hope his ageing squad can match England’s intensity. Argentina have shown that while they may not always dominate physically, their aerial prowess has improved—after scoring no headed goals in Qatar, they have already notched three in this tournament. Combined with their mental toughness, they may believe that success will once again come from using their heads—both literally and figuratively.