Robbie Neilson’s men will make the trip to Ayrshire in January determined to avoid a repeat of last season’s calamitous exit at the hands of Highland League Brora Rangers.
Hearts have faced Auchinleck twice before in the cup – each time getting through and ultimately reaching the final.
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But the Ayrshire side, formerly giants of the junior game but now competing in the West of Scotland League as part of the pyramid, will certainly be no pushovers at Beechwood Park.
They knocked out Championship side Hamilton at the weekend and have also dispatched of Ayr United in the recent past.
Hearts scraped through 1-0 at Tynecastle when the teams first met in 2012. Souttar played when they met again at Tynecastle in 2019, Hearts winning 4-0.
Souttar said: “We played them in 2019 when we reached the final. If we could do that again it would be brilliant, but it won’t be an easy game.
“You saw at the weekend that they can cause an upset, so we’ll need to be on our game and not take it lightly.
“I’ll look forward to it. I look forward to plaing at different grounds. I’ve never played there before, so it will be a nice experience for myself.”
Edinburgh City overcame Bo’ness United from the Lowland League and Lothian Thistle Hutchison Vale from the East of Scotland League to reach the fourth round.
Their reward, a trip to Pittodrie, will be the biggest cup tie in club’s history and should be a decent pay day for the League 2 club.
Elsewhere, Livingston have been drawn at home to Ross County in an all Premiership tie at the Tony Macaroni Arena.
Rangers are at home to Stirling Albion, who knocked out Tranent. Celtic travel to Alloa, who beat Bonnyrigg Rose at the weekend.
The ties are due to be played on the weekend on January 22, in the first matches after the cinch Premiership winter break.