By Gabriel Araujo KANSAS CITY, Missouri, July 4 (Reuters) - Argentina advanced to the World Cup last 16 with a 3-2 extra-time victory over Cape Verde, but the reigning champions left the match with new doubts after being pushed to the brink by the tournament debutants.

The reigning champs aim to punch their ticket to the round of 16 against the biggest surprises of the tournament

Lionel Messi, at age 39, leads the World Cup Golden Boot race with seven goals after his first-half goal vs. Cape Verde on Friday in Miami.

Leo Messi has done it again, scoring his seventh goal of the tournament with a left-footed strike in the first half of Argentina's round of 32 match with Cape Verde.

Another effort like this may have the defending World Cup champs home earlier than they expect. Argentina star Lionel Messi warned his teammates after Friday’s thrilling 3-2 win in extra time against live underdog Cape Verde that they put many “bad” things on tape in the Round of 32.

Lionel Messi scored his seventh World Cup goal to help Argentina beat Cape Verde