And the events of Sunday and Monday surely add at least a bit of intrigue to Argentina's plans.
Messi underwent testing on Monday (Tuesday AEST) — which almost certainly means an MRI exam, though the team did not divulge what procedures were involved — and was ultimately diagnosed with "an overload associated with muscle fatigue in his left hamstring" that kept him from finishing Inter Miami's match against Philadelphia.
"The timeline for his return to physical activity will depend on his clinical and functional progress," Inter Miami said in a release.
Messi was subbed out of Sunday's match against the Union in the 73rd minute. He essentially stopped playing a couple of minutes earlier and was seen grabbing at the back of his left leg at least once before he was substituted.
The 38-year-old forward walked off the field without any assistance and went directly to the team's locker room. Inter Miami, the defending MLS champions, won the game 6-4 and Messi had a pair of assists in the first half.
Heavy rain fell during the second half, leaving the field slippery, but it was unknown if the conditions were involved in the decision for him to leave the match. All the team said Monday was he was subbed out because of "physical discomfort."
Argentina have a pair of friendlies scheduled in advance of the World Cup, first on June 6 in Texas against Honduras and then on June 9 in Alabama against Iceland.
Lionel Scaloni's side are in Group J for the World Cup and will face Algeria in Kansas City on June 16, Austria at Arlington on June 22 and Jordan also in Texas on June 27.
Messi has already appeared in five World Cups, winning the Golden Ball as the tournament's best player twice — first in 2014, then again in 2022 when he led the Albiceleste to the title. That award has been given out only since 1982, but he is the lone player to win it twice.
