The implication from the film's original script is that Will (and the other players) have been playing for several hours. The hand that we see played is quite literally the final hand of the evening, strongly implying that at the point that we return to the action Will has already doubled his time, presumably by winning several smaller hands.
Note that the script shows a dissolve (usually intended to show the passage of time) rather than a cut.
Will looks to the poker tables
WILL: What's the limit?
HOST: There is none.
INT. CASINO - POKER TABLE. NIGHT.
Close on a TIMEPIECE in the center of the poker table flashes with SIX
HUNDRED YEARS and change.
and the thought process of the other players
Sylvia stares at Will, astonished at the risk he just took - finally
breaks her stare as Philippe rises from the table. The other players
follow suit - they have also had enough.
PHILIPPE: I think you've taken enough years off my life for one evening (extending his hand) Philippe Weil.
WILL: Will Salas.