The former Barca winger believes the Spanish capital club have much to improve upon, while insisting that only two sides can challenge for the title this season
The Bernabeu outfit have collected just one point from their last two league games as a 1-0 defeat at Levante and a goalless draw against Racing Santander have left them five points off the top of the Primera Division table.
Since the 6-0 mauling at Zaragoza, Madrid have struggled to impress, and Rexach, who played for Barcelona from 1967 to 1981 and was an assistant to Johan Cruyff during the Catalan club's Dream Team era, believes the Copa del Rey holders are not doing enough to justify their credentials.
"You cannot say they lack attitude, but they are far from playing like a big team," he is quoted as saying by Marca.
"They play like a small team and with the players they have, they should play with less aggressiveness and more possession of the ball."
The 64-year-old agrees with the notion La Liga is a two-horse race between Barcelona and Real Madrid, saying: "No matter what people say, this is league of two teams, though Valencia got off to a very good start.
"It is still too soon. Let us give it some time and wait for the first third of the league to be completed to speculate."