The winners will play Inverness, fifth in the Championship, in one semi-final while Rangers or Aberdeen face holders Celtic in the other on the weekend of April 13 and 14.

Caldwell said: "I saw Inverness (against Dundee United) and they probably had the best display of all the quarters. They're a very good team but we have a huge task first.

"I know the players know how difficult Tynecastle is and we have to be ready for the physical challenge and to be brave on the ball and cause them problems."

If Rangers overcome Aberdeen at Ibrox in a replay they will play their Old Firm rivals in the semi-final for the fourth successive season.

In 2016, the Light Blues won on penalties before losing to Hibernian in the final, with the Hoops winning 2-0 in 2017 and 4-0 in 2018 as they won the domestic treble in both seasons.

Caldwell is hoping the boost from the draw can be taken into their league performances.

He said: "We've had one-and-a-half bad games since January 1, so tonight was massive in putting those games to bed.

"This is a good team that has only lost twice since January.

"We have to keep playing like that in the league but it should give the players huge confidence and belief they can do that the rest of the season."

Hearts boss Craig Levein, speaking before the draw was made, insisted that his powerful striker Uche Ikpeazu should have been awarded a penalty at 1-1 when he was challenged by Gary Harkins inside the box.

Levein said:  "I really feel sorry for Uche. Just because he's stronger people shouldn't be allowed to foul him.

"I don't care what way you go down, if you get fouled it's a penalty.

"I don't want to start telling him to go down. He's a strong boy and he should get an even break.

"If he's stronger it's not a foul, but he constantly gets pulled up because he's stronger than others.

"I feel for him because you look at his performance he gives me everything you look for as a manager every week. He just doesn't get an even break."

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