Ange Postecoglou reckons the match-winning introduction of James Forrest shows how far Celtic have come in his tenure and now have the depth to introduce decisive quality.

The Aussie boss watched on as his side huffed and puffed against a brilliantly organised St Johnstone block.

While Jota and Kyogo struggled manfully to break it down, Postecoglou took the decision to introduce his veteran forward into the fray after an hour with almost immediate results.

It took Forrest just five minutes to open the scoring with a terrific finish that left Zander Clark stranded.

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And the Celtic manager was delighted given the 30-year-old's recent struggles with injury.

He told Premier Sports: “(It’s)Brilliant for him. He hasn’t had the greatest start to this season but I’ve had no doubt that once we got him fit and feeling good about his own body he could contribute to how we play our football.

“He’s and experienced and high quality player and he’s in that spot to get that goal, I’m pleased for him.

“It also shows our progression in terms of being able to throw people like James on which we couldn’t do at the beginning of the season to change games for us.”

The Celtic supporters haven’t been at Hampden for some time given COVID but they didn’t half make up for it, creating a din for the ages and paying passionate tribute to Lisbon Lion Bertie Auld who passed away last week.

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And the manager was happy to wax lyrical about the atmosphere created as the old Mount Florida ground creaked amid the thunderous din.

He said: “It was brilliant. I thought it was fantastic. They have missed coming here and missed us being here.

“I thought it was really special all night.”