The 36-year-old veteran of three World Cups with Argentina is suspended after being sent off in last weekend's 1-0 win at Huracan that put River alongside four other teams at the top of the Apertura championship after two matches.
When Ortega, who has a known drinking problem, missed Tuesday's practice there were fears of a relapse without a match to prepare for.
But Ortega turned up for training on Thursday saying he had got over a minor injury and felt 100 percent.
His unavailability, though, gives coach Angel Cappa the problem of finding the right replacement for River's best player of the opening matches of the season.
Ortega laid on the stoppage-time goal that gave River a 1-0 win over Tigre in their opening match and was at the heart of their best moves at Huracan.
Cappa may mow look more to 22-year-old Diego Buonanotte, an Olympic gold medal winner with Argentina in Beijing in 2008, to create opening against Independiente.
ABOVE-AVERAGE ALMEYDA
A victory at their Monumental stadium would further cement River's fight against a poor relegation average and raise hopes of playing for their first title since the 2007/08 Clausura.
In the two years since that championship, River have been at their lowest ebb ever with relegation, decided on a points average over three seasons, a very real threat.
At the beginning of this season, they were bottom of the averages with only the three promoted teams potentially lower.
They owe much of their new-found solidity to the fine form of another World Cup veteran, 36-year-old defensive midfielder Matias Almeyda who was in the Argentina team with Ortega at France 98 and Korea/Japan 2002.
"Our mentality is to win. We have to play each match like a final," Almeyda told reporters.
"I never understood the business of the averages. For me it's like a race, you take off and have to win, not look back. Winning you get the largest number of points and so fight for the championship."
Independiente, whose last title was the 2002 Apertura, have only picked up one point to River's six as they rebuild under new coach Daniel Garnero having vied for last season's Clausura until the closing matches in May.
They won both teams' meetings last season with a 2-0 victory at the Monumental in March.
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