Ange Postecoglou is looking for Celtic to use the disappointment of a Scottish FA Cup exit to fuel their title bid.
Celtic's Carl Starfelt put through his own net deep into extra-time as Rangers came from behind to beat their Old Firm rivals 2-1 in a frantic semi-final.
Greg Taylor fired a low finish beyond Jon McLaughlin shortly after the hour to hand Celtic the lead, before Rangers substitute Scott Arfield bent home a brilliant leveller to force additional time.
With a penalty shoot-out on the horizon, Starfelt deflected Calvin Bassey's left-wing cross past Joe Hart to send Rangers to their 53rd Scottish Cup final, where Hearts lie in wait after overcoming Hibernian.
"We have had to be resilient all year and this is another challenge for us," the Hoops' Australian coach said.
"We are disappointed we didn't get to another final, we are disappointed for our fans.
"But irrespective of what happened today we have five games to concentrate on winning the league, starting next week.
"We need to make sure that we use this disappointment to fuel our endeavours in this next series of games."
Giovanni van Bronckhorst praised his Rangers side's "phenomenal" character.
"It was a very proud moment for me to see my side play like that," he said.
"We had to dig deep after a demanding game against Braga. But I think today our character was phenomenal, especially because we knew that Celtic were coming at us fresh. The guys did terrific."
Van Bronckhorst believes the win gives Rangers incentive to go on and win the cup for the first time since 2009 while they continue their pursuit of Celtic at the top of the league.
- with DPA
Australian Associated Press