To reach the semis, the Tangerines will have to do what no other Scottish side has done since November.

That’s the last time the runaway league leaders and Co-Op Cup finalists lost a domestic fixture — 1-0 at Aberdeen — and the United gaffer sees that stat as the measure of a very good side.

“We know how hard Sunday is going to be, because we are up against a team who have been playing very well in most of their games and, even when they haven’t, they don’t give away goals,” he said.

“They’re flying in the league and it is never easy at Ibrox, so we know how hard it will be, but I don’t think what happened before is going to have an affect on the players.

“I don’t want to tempt fate, but that was a freak result and I do not see that happening to this team again.

“There were a few factors. I think the whole club was a bit down after Craig (Levein) left for Scotland and we just had a very bad night.

“The players have responded magnificently since and, hard as this tie is for us, I have complete confidence they can go through on Sunday and give a good account of themselves.”

Striker Francisco Sandaza, meanwhile, might not feature in the Sunday lunchtime tie.

United are being very cautious about his recovery from the double hernia that delayed his first appearance of the season until the final few minutes of Sunday’s win over Hearts.

He has been suffering from tight hamstrings and that’s seen him spend most of this week doing light work under the supervision of the physio.

“It’s not unusual when you’ve been out for as long as he has for this to happen and we are taking things very carefully with him,” added Houstie.

“It’s not a big issue, because he is still a good bit away from being fit enough to be considered for a starting place.”

That news won’t prompt a Hearts style reaction — they dropped Jose Goncalves when he said he was leaving — from the Dark Blues boss.

Today, Jocky revealed he has complete faith in MacKenzie to remain 100% focused and help Dundee to league and maybe even Scottish Cup success.

“To be honest, this is something I’ve known about for weeks and, just because it has been made public, I don’t see any reason to change anything,” he said.

“When big Gary told me about his decision, we had a chat and I told him, as far as I was concerned, the best thing for him to do was make sure he was going down there as not just another player but as a winner with medals.

“That’s exactly his attitude and you’ve seen that in games. I know it’s not going to change — he’s been having a very good season and I believe it’ll continue.”

While he’s disappointed to be losing the 24-year-old former Ranger, Jocky admitted he could not be critical of his reasons for moving.

“I’m one who’s had a go about players chasing money, but I know what we were offering was pretty much the same as MK Dons.

“He wants the challenge of a different league and, if he is going to develop into a Championship or even Premiership centre-half, he’s a better chance of being noticed if he’s in the lower leagues down south. He’s big and strong, and fits the bill for down there. I’m not going to have a go at him for wanting to further his career.”

Meanwhile, if MacKenzie’s central defensive partnership with Jim Lauchlan is going to be broken in Saturday’s cup quarter-final against Raith Rovers, it’s likely to be via the return of Craig McKeown than the introduction of new boy Bob Malcolm.

Clearance has finally come through from Australia for him, but a lack of match fitness is a problem.

“We didn’t get our closed-door game against St Johnstone this week because they had a few injuries and, although we had a bounce game in training, that’s not the same,” explained Jocky.

“Malcolm did OK, but he is still building his fitness and that’s something for me to think about. McKeown is also lacking games, but he’s been training hard for a few weeks and I can consider him for a start.”