Cape Town - As if no wins in three matches wasn't enough of a concern for City manager Manuel Pellegrini, he also saw playmaker David Silva limp off against Newcastle with a twisted knee.
The absence of Silva would be a major blow for City, with the Spain international one of the team's best players in its inauspicious start to the season.
Fellow playmaker Samir Nasri returned against Newcastle after six weeks out but isn't up to full speed.
City will rely heavily on Sergio Aguero, the Premier League's joint top scorer, for goals.
For all of the attacking might on show on Sunday, there will be just as much scrutiny on defenses that have kept just two clean sheets each this campaign.
City manager Manuel Pellegrini focused on strengthening his defense in the offseason by signing right back Bacary Sagna on a free transfer and center back Eliaquim Mangala for £32 million pounds, as well as a defensive midfielder in Fernando.
But Pellegrini has not yet settled on a regular back four as he integrates his new signings and Mangala, English football's most expensive defender, is struggling to adapt.
Van Gaal has had to contend with a slew of defensive injuries that saw him first try a three-man defense and then revert to four at the back. He hasn't fielded the same defense two matches running and Phil Jones is now sidelined with shin splints.
While United's attack looks strong, the defense remains a work in progress. It means there shouldn't be a shortage of goals at the Etihad.
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