The England international started in the Arsenal back three alongside Shkodran Mustafi and Sokratis Papastathopoulos following their brilliant 4-2 win over Spurs in the north London derby last weekend.
However, Holding was forced off in the first half after lengthy treatment on the sidelines following a clash with Manchester United striker Marcus Rashford.
The 23-year-old was carried off on a stretcher to suggest that the suspected knee problem could be serious, with NBC Sport pundit Lee Dixon confirming that Holding underwent a scan at half-time during his commentary on American television.
Speaking at his post-match media conference after Arsenal’s 2-2 draw at Manchester United, Emery confirmed that Holding had suffered a serious injury setback.
“The worst news is the Rob Holding injury, the doctors think maybe it is a big injury but we are going to wait (to find out). It is his knee,” Emery said.
Ramsey, who started the Premier League clash with the captain’s armband, was also substituted at half-time following a knock.
However, Emery reassured Arsenal supporters that the midfielder’s injury didn’t appear to be serious.
Emery added: “Ramsey I think is a small injury but they showed us that afterwards every player responded with a good quality.”
Arsenal broke the deadlock thanks to Mustafi’s header in the 26th minute, but Anthony Martial levelled four minutes later to leave the score at 1-1 at the break.
The Gunners were ahead in the second half through Alexandre Lacazette but less than a minute later, Jesse Lingard equalised for the home side to deny Arsenal successive victories against their top-six rivals.
Emery’s side will take on Huddersfield Town at The Emirates in their next Premier League fixture on Saturday afternoon.
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