After being knocked unconscious for Switzerland during the international break - and then inexplicably having been allowed to play on - Fabian Schar underwent cognitive tests upon his return to Tyneside.
The centre-back returned to light training a week ago, but further assessments were set to take place to ensure he had overcome the after-effects of potential concussion.
So is Schar fit to return to the Newcastle side? And, if so, will he come straight back into the starting line-up after serving his two-match ban for picking up 10 bookings?
Isaac Hayden has been one of Newcastle's most-consistent performers throughout 2019, but the midfielder picked up a hip injury during the first half of the defeat to Arsenal.
Having initially tried to play on, Hayden was replaced during the second half by Ki Sung-yueng - and Jonjo Shelvey was left on the bench as an unused substitute.
Is Hayden fit to face Palace tomorrow? And, if not, who will Benitez turn to instead? Could Shelvey finally earn his first Premier League start of 2019?