Rubens Sambueza - A left midfielder, created by River's lower divisions. He made his debut in January 2004 and left everyone shocked by his talents. Unfortunately, he has never been able to live up to his hype. He has had great games, such as the ones vs. Corinthians in the Copa Sudamericana 2005 or vs. Boca in the Torneo de Veranos 2004 & 2007, but is irregular during the season. He hasn't impressed in any of the 4 season games so far. He has talent, though. If anyone gets the best out of him, he can become a very valuable player.
Victor Zapata - What I say? He's one of my least favorite players to ever dress a River jersey. Victor plays on the left side and supports more to the defense than to the offense. Maybe taking his position and giving it to Sambueza is what he needed, because the two games he played were great (entered as a sub in both). If he keeps up that level, he could be a fantastic player. (Note: That would be very doubtful).
Fernando Belluschi - Fernando can play on the right side, as a "double 5", or as a playmaker. Belluschi is, arguable, River's best and most important player. He jukes fairly well, but his specialties are giving amazing passes and beautiful shots. The team somewhat revolves around him, and he has shown his importance in tough matches, such as vs. Boca in the 3-1 for the Torneo Apertura 2006. Big clubs like Atletico Madrid have offered over $12 million euros for him, but River automatically rejected those offers. Upon hearing that clubs like Real Madrid and Barcelona were after him, Passarella saild he was worth 30 to 40 million dollars.
Augusto Fernandez - A huge promise for the future, atleast in my opinion. Fast, young, good dribbling skills, nice definition: Augusto has all it takes to succeed in River. He plays on the right side and is very similar to Lucho Gonzalez. It is not a coincidence that Barcelona and Villarreal were interested in him in the past. For now, he is a substitute.
Diego Galvan - Despite not having everyone place their confidence in him at first, he's been doing a great job. Diego plays on the right side and never gets tired of running. He joined River from (the now B-Division side) Olimpo in 2005. After an unsuccessful first season with Los Millonarios, he was loaned to Estudiantes (LP) for a year and was an important part of their 2006 Apertura tournament win. He returned in January and has gained himself a spot in the first team.