League form, currently poor for both teams, will have little bearing on what could be one of the more exciting encounters between the bitter enemies in recent times.
River, on the back of their 2-0 home win over Huracan last Saturday, fancy their chances of winning the "Superclasico" in the 50,000-capacity Bombonera cauldron.
They have not won there in four visits since 2004 when they triumphed 1-0 during coach Leonardo Astrada's previous spell in charge with a goal by striker Fernando Cavenaghi, now playing for French champions Bordeaux.
Boca, humiliated 3-0 by modest Tigre on Sunday when they were eclipsed by a Carlos Luna hat-trick, have been juggling with their line-up for weeks, sometimes favouring experienced veterans and sometimes raw youth.
Coach Abel Alves, whose job is on the line, has no hesitation in fielding 36-year-old Argentina striker Martin Palermo or playmaker Juan Roman Riquelme, two players who can settle a match with a stroke of inspiration.
"We are Boca, even if they're giving us up as dead, and at some point we're going to react. I'm confident it will be on Sunday," Palermo, who needs one goal to break the club record of 218 he holds jointly with 1930s striker Roberto Cherro, told reporters.
"I'd love Boca to finish bottom (of the championship table)," said River midfielder Oscar Ahumada with obvious glee.
WORST DEFENCE
Boca, South American champions four times in the last decade, are 17th of the 20 teams in the standings after one win in nine games and seven matches without a victory, conceding an average of two goals a game, the top flight's worst record.
River are not much better placed in 11th, four points ahead of Boca with three wins but eight points behind leaders Independiente in the short, 19-match Clausura championship, the second of two in the season.
Astrada has faith in two of his trio of veterans, midfielders Marcelo Gallardo and Matias Almeyda, but forward Ariel Ortega has lost his place as a result of off-field problems related to a drink habit.
The "Superclasico" has joined tango, polo and the Recoleta cemetery where figures such as Evita are buried as a major tourist attraction in 21st-century Buenos Aires with a match package that includes transportation to the Bombonera, a tour of the stadium and Boca's museum and a well-placed seat going for $400.
The meagre 4,000 tickets provided to River's visiting fans for sale online went in two minutes. River, the team whose fans travel in greatest numbers to away matches, had asked for double the number but were turned down, probably for security reasons - a major issue in a league marred by hooligan violence.
