Luan is nursing a foot injury while Everton is struggling to recover from a thigh problem that forced him out of Brazil's international friendlies against Saudi Arabia and Argentina earlier this month.

Gremio could also be without veteran right-back Leo Moura, who has a calf complaint.

Wednesday's clash at the Bombonera features two teams that have had vastly different fortunes in the Copa Libertadores.

Palmeiras, the most successful club in Brazil's Serie A history with nine titles, have won just one Copa Libertadores title: in 1999 during Scolari's first spell as coach. They were losing finalists to Boca Juniors the following year but have mostly struggled in the competition since then.

Boca, meanwhile, are six-time Copa Libertadores champions and could this year equal Independiente's record as the club with the most titles.

Palmeiras have been rejuvenated under Scolari, who returned to coach the club for a third time in late July. Since then the Sao Paulo outfit have won 16 and lost just two of their 23 matches in all competitions and they currently hold a four-point buffer at the top of Brazil's Serie A standings.

Conversely, Boca have struggled to recapture the form that saw them win the past two Superliga Argentina titles. Guillermo Barros Schelotto's men are currently fifth in the Superliga standings with just four wins from nine matches this season.?

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