FOXBOROUGH, Mass. -- For the thousands of Americans that have spent June cheering Lionel Messi’s name and imploring him to wow them, it may be a case of “be careful what you wish for.” Argentina, with Messi in the starting lineup for the first time, eliminated Venezuela from the Copa America Centenario on Saturday night and will now be gunning for the tournament hosts.

Whether he’s been on the pitch or sat on the bench, Messi has been the center of attention all month.  In Argentina’s opening game, against Chile at the Levi’s Stadium, his name was chanted relentlessly even though he played no part, and despite a fine performance in its own right by Angel Di Maria.

In the second game, against Panama at Soldier Field, he was given a 30-minute run-out in which he scored a fine hat trick. It was something only Messi could do and it made for a night that the fans present, many of whom had come just to see the world’s best player, will never forget. Those who flocked to Santa Clara will curse their luck for the rest of their lives at having chosen the wrong night.

There was plenty of love for him in Seattle, too. He was still not fit enough to start against Bolivia but, as ever, even a sight of him on the big screens brought about bigger cheers than any goal scored by any other player.

Here, in Foxborough, he was handed his first start, and within eight minutes showed once again what all the fuss is about. Picking up the ball on the left-hand side, he took two steps infield and launched a millimeter-perfect pass for Gonzalo Higuain. The Napoli striker showed great anticipation to even get into the right spot, but when you play with Messi it must become routine to expect the unexpected. The finish was clinical, too, and he made no mistake 20 minutes later when he seized upon a dreadful backpass from Arquimedes Figuera to round keeper Dani Hernandez and slot home for 2-0.

cannot yet be considered shoe-ins to win this competition, even if they deserve their reputation as favorites. Venezuela, undone by a piece of Messi genius and their own uncharacteristic sloppiness, set about mounting a comeback and had Tata Martino’s men on the ropes.

But for Sergio Romero, the Vinotinto may have even been level before halftime. The Manchester United keeper, consigned to the bench since September, showed his best form to deny Salomon Rondon with a strong right arm, and then brilliantly tipped Rolf Feltscher’s deflected effort over the bar. Romero was well beaten by a Rondon header, but the burly striker’s effort came back off the upright.

Once again, though, the Venezuelans proved to be their own worst enemy when it came to the crunch. Awarded a penalty when Romero dived into Josef Martinez at the near post, Luis Seijas elected for a terribly executed Panenka which the grateful keeper comfortably clutched to his chest.

Less than 15 minutes into the second half, Messi made them pay. After a slick one-two with Nico Gaitan, he coolly put the ball through the keeper’s legs and into the back of the net. On Tuesday he was criticized in some quarters for nut-megging Bolivia’s No. 1 when the play was dead. Here, though, he did it for all the right reasons, and in the process equalled Gabriel Batistuta's Argentina goal-scoring record.

And it served as a warning, if one were needed: you just can’t give away goals and miss penalties against this Argentina. Venezuela did eventually get on the scoresheet through a Rondon header, but Erik Lamela struck so quickly in reply the stadium announcers did not have time to announce the consolation. Either way, the damage had been done.

But while it is too late for Venezuela, there are other teams who will take heart that Martino’s men can be got at, and that this tournament is far from a foregone conclusion.

The U.S. will be the first to take note. Jurgen Klinsmann’s men sealed their passage to the last four on Thursday night (48 hours earlier than their opponents, representing a huge advantage), and will approach the match in Houston knowing that they should have chances to score – even if, admittedly, it will require an almighty effort

But the main issue, of course, is how to cope with Messi. Even when less than fully fit he made a hat trick look easy and most likely welcomed aboard many more fans to the bandwagon. Now he is back at 100 percent, and few teams have ever been capable of living with him in this kind of form. 

Indeed, it will be interesting to see whether those American fans who have turned up in Argentina shirts so far this summer switch continue to cheer for Messi et al, even against their homeland. Those in the U.S. corner, however, should be fearful of what comes next.