He lunged in on Juan Sara having been booked for an aerial challenge on the Argentinian striker. It was senseless and Moore will know it and now Rangers really have a challenge on their hands to claim second place.
Celtic’s win at Perth simply underlined that the title is off to Parkhead but Rangers simply cannot contemplate losing the runners-up tag to Hibs.
Moore is out of Saturday’s trip to Motherwell and sadly man of the match Lorenzo Amoruso will also miss that game having had to limp off with what looked like a bad knee injury.
This nightmarish season just gets worse and worse, but there was a final twist as Dundee sub Steven Milne scored a second goal in injury time. It was hardly the ideal night for Marcus Gayle to come into the side but he cannot be blamed for what happened.
Gayle was in the starting line-up as expected, following his £900,000 move from Wimbledon, but sadly there was no place for Frenchman Fabrice Fernandes as clearance for his loan move did not come through in time.
Gayle, though, was keen to make an impact and certainly put himself about, forcing Marco Roccati to save his header just before half-time, but he and Rangers were fighting to get back into the game by that stage.
Incredibly, Dundee found themselves in front after only 13 minutes and it was South American superstar Caniggia who did the damage with an accurate strike.
Georgian midfielder Georgi Nemsadze orchestrated the move as he burst forward to release Caniggia who had peeled away on the right side of the box. The Argentinian took one touch and drilled a right foot shot which squeezed into the net off the right hand post.
It was a killer blow to Rangers, but they almost equalised within 60 seconds. It was Gayle who created the chance with a superb ball inside fullback Barry Smith which released young Ulsterman Steven Carson clear on keeper Roccati.
Carson, making his first start for the club, should have scored but he aimed his shot straight at the Italian keeper who was able to make a blocking save. Had he scored he might not have been replaced by Billy Dodds at half-time.
Rangers were in good position again in 26 minutes when a wonderful Barry Ferguson pass sent Tore Andre Flo scampering down the right side with time and space. Gayle and Carson waited in the middle but Roccati cut out Flo’s cross.
However, the Ibrox men were almost caught out again in 30 minutes. Javier Artero’s cross was only half-cleared by Scott Wilson and Juan Sara struck a powerful right foot strike which Stefan Klos saved well.
Dundee were in again in 38 minutes and, alarmingly for Rangers, it was an even better chance. Artero picked out Caniggia on the right and his cross was perfect for Gavin Rae but he shot wide when he should have scored.
It was looking like another uncomfortable night for Rangers, who simply could not afford anything other than a win, and their task was made infinitely more difficult by the reckless behaviour of Moore.
There is some doubt as to whether the Australian’s challenge on Sara a minute into the second half merited a yellow card. He merely went for a header like any defender would and his momentum took his arm through on the striker.
Moore, though, did not take the decision and get on with it. Two minutes later he made a ludicrous lunge on the same player and Rowbotham had no option but to issue a second yellow and therfore a red.
With all of their injuries, the last thing Rangers need is suspension problems and Moore has ruled himself out of Saturday’s Motherwell game and that must infuriate Advocaat.
Advocaat, needing another defender, put on Bob Malcolm for Allan Johnston but Rangers had Klos to thank for preventing a second goal in 52 minutes as Dundee exposed Rangers on the breakaway.
It was Rae who created the chance, bursting from his own half to release Caniggia but Klos got his angles absolutely right and stood up so well to block the Argentinian’s shot.
Rangers, urged on by Lorenzo Amoruso and Barry Ferguson, battled to get back and while they had plenty of the ball they seemed unable to create the chances they needed.
Flo shot over the bar in 56 minutes and then had a header wide in 70 minutes but it just was not happening for the Ibrox men, who were heading for their first home defeat since October.
And just to compound a quite awful night, Amoruso had to be helped from the field six minutes from time with what looked like a serious knee injury. The former captain looked in some pain as he was helped round the track by doctor Gert Jan Goudswaard and physio Gordon Allison and it summed up Rangers’ night.
The agony was not over, however, as Dundee scored a second goal in injury time when susbtitute Steven Milne’s shot hit Klos on the right arm and flew into the left corner.
If the title was not already lost before this match it most certainly is now. However, of more importance to Rangers is the chase for second place and that is undoubtedly got some distance to go.
RANGERS: Klos; Moore, Wilson, Amoruso (Kauppila 84), Porrini; Johnston (Malcolm 50), Konterman, Ferguson, Carson (Dodds 45); Flo, Gayle. Subs not used – Christiansen, Leven.
Sent off: Moore (48)
Bookings: Wilson (42), Ferguson (53)
DUNDEE: Roccati; Smith, Coyne, Tweed, Marrocco; Artero, Nemsadze (del Rio 90), Rae, Garrido; Sara (Milne 86), Canniggia. Subs not used – Langfield, Robertson, Russo.
Bookings: Caniggia (49), Smith (62)
Ref: John Rowbotham.
Att: 45,035
Man of the match: Lorenzo Amoruso
Moment of the match: Gayle’s exquisite through ball for Steven Carson.