It was most likely shaped window light, not a separate hidden key light. The catchlight suggests a large window source, but the stronger shadow and falloff on camera-right can be created by negative fill: black cards, flags, or V-flats placed close to the subject to absorb bounced light and stop the window from wrapping evenly around the face.

One answer notes that in the eye reflection you can make out an area on camera-right with little or no reflection, consistent with a flag blocking light, and possibly another flag overhead. Another points to the making-of video, where Cruz is surrounded by black cards; as she moves, the falloff increases quickly, which fits a close large source plus negative fill.

So the likely setup is a large window as the main light, with black cards/flags used to control spill and deepen the shadow side, rather than a separate facial light. Moving the subject closer or farther from the window and from the black cards would change how much the light wraps.