Claridge haunts faltering Woves
In the biggest game of the First Division season so far, Wolves's defeat not only gives Kevin Keegan's side Premiership football this season, but means their deadly rivals West Bromwich Albion can go above them if they get anything from their home fixture with Rotherham on Sunday.
For Millwall, the result was also crucial as this victory goes a long way to helping them secure a play-off berth.
The veteran striker, who turns 36 next week, was a hate figure during his time at Wolves and booed throughout the game by the travelling fans but certainly had the last laugh with a penalty 17 minutes from time.
Claridge was brought down for the game's only goal by Shaun Newton - Wolves's best player on the night - and coolly slotted home from 12 yards sending Michael Oakes the wrong way.
Dean Sturridge came within inches of equalising in the 90th minute when he met George Ndah's superb inswinging ball from the right flank with a sharp first time effort but the ball came back off Tony Warner's right hand post.
Wolves now have not won in their last seven games and face a tough game against Wimbledon next time out, though in truth their supporters can have had little complaint with their performance at the New Den.
In a pulsating contest they had numerous chances but found Warner in superb form in the Lions goal and were themselves wasteful in front of goal.
Twice the former Liverpool apprentice denied Colin Cameron from close range with sprawling saves after superb work on the flank from Newton.
The Lions had the better of possession throughout the game but had less clearcut chances.
Republic of Ireland international Stephen Reid, who put in a superb performance on the left hand side of midfield, went close twice in the first half, first with a back post header that narrowly evaded the target in the third minute and then with a thunderbolt long range effort that Oakes just managed to hold.
Just before the break, former Lion Alex Rae ran through on goal but just slipped his effort wide of the target before getting clattered by the Millwall keeper for his troubles.
In the second half, Wolves began well but if anything Millwall looked more potent on the break and the visitors were on the receiving end of two fortunate refereeing decisions before the break.
Kevin Cooper was fortunate not to be dismissed for a nasty challenge on Kevin Lawrence.
Minutes later Paul Ifill was brought down in the penalty area by Mohamed Camara but a free kick was instead given just on the edge of the box.
Justice was done 17 minutes from time though, when the South London side were awarded the spot kick and Claridge certainly made no mistake.
There then followed a nervous twenty minutes for the home side, especially after Ndah and then Nathan Blake were added to the visitors' forward line but Mark McGhee's side held on gamely, showing character that could serve them well in the play-offs.
For Wolves, they face a nervous wait to see how their neighbours get on on Sunday and the thoughts of their fans will undoubtedly be turning to the numerous occasions they have narrowly missed out on promotion to the top-flight over the last decade.
Click below for match analysis and an updated table:
Millwall v Wolves