As his former partner in crime at Liverpool, Robbie Fowler, made off with the match-ball after his stunning hat-trick in this pulsating encounter, Collymore was in the dock again following the second dismissal of his troubled career with the Premiership leaders.
On the first count, of the reckless high challenge which ended Steve Harkness' part in proceedings and saw him leave Villa Park on crutches with damaged knee ligaments, there was no doubt of the pounds 7m striker's guilt, even if Peter Jones wrongly viewed it as meriting no more than a yellow card.
However, it was Collymore's irresponsible reaction to being fouled by Michael Owen, at a time when Villa were still making chances, that means he should also stand accused of betraying the trust Gregory placed in him after the summer assault on Ulrika Jonsson.
There is also a third, related charge: that Collymore is incapable of learning from his mistakes, and as such is a liability to his team.
Gregory, with a candour from which Alex Ferguson and George Graham could learn, readily conceded that Collymore was "lucky to stay on" after fouling Harkness. Contradicting his own player, he added that the incident was indeed a hangover from the clubs' previous meeting, when Collymore accused Harkness of racist abuse.
But when Gregory pleaded mitigating circumstances and rejected the concept of Collymore as the rotten apple, he was demonstrating misplaced loyalty. The Villa manager's argument was that it is hard to restrain yourself after a two-footed lunge such as Owen inflicted two minutes after Liverpool closed the scoring.
Collymore's response, which was to grab his ex-colleague round the neck and push him away, did not warrant a second booking, felt Gregory: "I hope it's just a hiccup for Stan. Until now he's worked very hard and helped to put us on top, and I won't overlook that fact.
"I'm pleased with the way he has knuckled down. A lesser man could have thrown it all in and said: `I don't need all this hassle, pay me off and I'll clear off.'"
Gregory also believes that the player's name, like that of Vinnie Jones or Julian Dicks, works against him. "I don't think Stan ever gets a free- kick in his favour. Referees allow people to kick him and climb all over him. They should look at him as a footballer, not as Stan Collymore."
Yet the evidence is damning. By Gregory's admission, he substituted Collymore on Liverpool's last visit to avoid his being sent off, while at Coventry this season his last-minute warning to him "not to get involved" was followed by a first-minute caution. There have been too few goals to balance out the indiscretions.
On this occasion, a Liverpool side already 2-0 up ought to have been facing 10 men for 82 minutes. As it turned out, Villa, who could have been 5-1 down by half-time, were shaken out of their shell-shocked state by the inspirational Paul Merson.
They could conceivably have stretched their unbeaten start to 13 games had David James not prevented Dion Dublin from equalling Fowler's haul with a fine penalty save with 14 minutes remaining. Liverpool, though, exposed Villa's vulnerability to quick, accurate passing, much as Celta Vigo did three weeks ago. The suspended Ian Taylor, who breaks things up in midfield, was badly missed.
The same could not be said of Steve McManaman's absence from Liverpool's line-up. Without his tendency to dribble aimlessly across the pitch, the build-up was altogether quicker. In another ironic twist, Gerard Houllier's first solo success was achieved with the long-abandoned 3-5-2 formation associated with Roy Evans, the Frenchman's objective surely being to shore up midfield.
Apart from Fowler - whose three goals, for the information of Glenn Hoddle and Andy Cole, came from four attempts - the passing and the passion behind Liverpool's victory were epitomised by Jamie Redknapp and Vegard Heggem respectively. With two-thirds of the season left, they could yet have a say in what Saturday's results indicate may be an unusually open title race.
Villa's capacity to stay the course will be clarified by matches against Manchester United, Chelsea and Arsenal in the space of nine days starting later this month. They must rediscover the ability to defend as a team, and concentrate on playing through opponents rather than succumbing to the temptation to pump long balls in the direction of Dublin's dome.
Composure and the ability to absorb harsh lessons do not, alas, come naturally to everyone, as Collymore's recurring problems show. Next weekend he faces another potentially fraught reunion with a club he left acrimoniously, Nottingham Forest. In the meantime, Gregory observed with an unfortunate choice of words: "Stan will be kicking himself."
Goals: Ince (2) 0-1; Fowler (7) 0-2; Dublin (47) 1-2; Fowler (58) 1-3; Dublin (64) 2-3; Fowler (66) 2-4.
Aston Villa (3-4-1-2): Oakes; Ehiogu, Southgate, Barry; Watson (Charles, 87), Draper (A Thompson, 51), Hendrie, Wright (Joachim, 75); Merson; Dublin, Collymore. Substitutes not used: Grayson; Rachel (gk).
Liverpool (3-5-2): James; Carragher, Staunton, Babb; Heggem, Ince, Redknapp, Berger (McAteer, 63), Harkness (Bjornebye, 12); Fowler, Owen (Riedle, 80). Substitutes not used: D Thompson, Friedel (gk).
Referee: P Jones (Loughborough).
Sending-off: Villa, Collymore. Bookings: Villa Collymore; Liverpool Redknapp, Owen, James, Babb.
Man of the match: Fowler.
Attendance: 39,241.Reuse content