Celtic manager Ange Postecoglou has praised midfielder Aaron Mooy, highlighting that his calmness under pressure is just as important as his football ability.

The 32-year-old opened the scoring at Tynecastle as the Hoops ran out 3-0 winners against Hearts to reach the semi-finals of the Scottish Cup.

It was his seventh goal of the season and the Parkhead boss was keen to lavish praise on the former Brighton man after the match.

Speaking to Celtic TV, he said: "He’s a good player, he’s a very good player. He’s a key contributor to us now.

"It is just as much about his ability as it is about his calmness and the knack he has for not letting the circumstances affect him.

"He has played at the highest level and you can see that quality.”

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John Hartson has posed whether the Premiership is strong enough after Celtic's comfortable win over Hearts this afternoon.

Hearts were without some big players, such as Lawrence Shankland, Robert Snodgrass, and Craig Halkett.

However, their performance in this one didn't merit anything close to a semi-final place in the Scottish Cup.

The gulf between Celtic and every other team in the league is clear to see. 

But Hartson has questioned the quality of the top-flight sides outside of the top three given that Celtic were streets ahead of Scotland's third-best team.

Hartson said on Viaplay Sports 1: “Hearts have a lot of injuries - missing their top scorer Lawrence Shankland and Robert Snodgrass who can make things happen, long-term injuries like Craig Halkett who is their leader - but saying all that they are still doing fantastically well.

“They are third in the league and maybe we need to look at the league. Is the league strong enough? Hearts are up to third and for me are the third-best team in Scotland but who else is really threatening Hearts right now?

"They are five points ahead of Hibs and way clear of other teams. Celtic, Rangers, and Hearts are the top three teams and the other teams have to do a lot more to catch up.

“Celtic march on. They are steamrolling everyone right now, they really are. They are 21 games unbeaten. They’re awesome. The one thing Hearts had to do - and I said it at the start of the game - was stay with Celtic.

“You can’t gift Celtic anything. In the first minute, Celtic got in behind and Reo Hatate had a really good shoot.

"Zander Clark made the save, and a minute later Celtic go a goal in front and all of a sudden Hearts have an awful lot to do.

"Hearts came back into the game with the Toby Sibbick chance but I can’t recall Joe Hart making another save in 90 minutes."