"....came too far out of the scoring circle, allowing Alonso to slip past and sneak a goal that took Brazil ten points ahead"
-- match report USA v Brazil, Daily Prophet, 4 July 2014 (Pm)
During their first game, only the brilliance of the Haitian National Team's Keeper kept the score close, before Haiti was disqualified for an illegal Snitch catch. The Brazilians then won their quarter-final match against the Welsh National Team by 460 points to 300. Their semi-final was a marathon against the USA team, which they won on the second day of play (Pm).
Prior to the semi-finals, Ludo Bagman had adjudged Alonso to be the "Outstanding player" from the Brazilian Team. The Daily Prophet felt that the Chasers from Brazil had been "one of the joys of the tournament". However, Brazil lost the final match to Bulgaria by 170 points to 60, following an exciting race for the Snitch by the two Seekers (Pm).
Other canon notes and references
Alejandra means "defender of men" and derives Old Greek alexein ("to ward off, defend") and aner ("man") (Baby Namespedia).
Alonso is a Spanish surname of Germanic origin (via the Visigoths), often used by Spanish royalty. It derives from the ancient name Adafuns (adal meaning "noble" and funs meaning "active, ready") (Surname Database).
As she comes from Brazil, Alonso may well have attended the Castelobruxo Wizarding School.
From the Web
Screenshots of the Daily Prophet's coverage of the 2014 Quidditch World Cup: http://imgur.com/a/AXutv