The predictable exit of pretty Hollie Cavanagh from American Idol was overshadowed tonight by an astonishing half time performance from Jennifer Lopez.

Astonishing for all the wrong reasons as the 42-year-old unleashed a cringeworthy PDA with her dancer boyfriend Casper Smart during a performance of new single Dance Again.

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Oversharing: Jennifer Lopez engaged in this astonishing PDA during her performance of Dance Again on American Idol tonight

Taking the stage in a sequin covered bodice and a pair of black tights, Lopez became the latest victim of ‘Madonna syndrome,’ an affliction belonging to female pop superstars over thirty which causes them to become allergic to wearing proper clothes on their bottom half.

See also, Christina Aguilera on The Voice this week.

Lopez, at least, looked fantastic, but she would have look equally incredible in trousers or a skirt and less like she’d been locked out of her dressing room while getting ready.

But the skimpy outfit’s purpose was revealed when Casper, 25 , pulled away from the rest of the backing dancers to perform alone with his older lover.

Their intimate moment: J-Lo and Casper get their moment to be alone… in front of millions of people

Making a point: J-Lo seemed keen to convince everyone who was watching that she’s blissfully in lust with Casper

Totally unnecessarily for everyone watching, the youngster grabbed the mother-of-two’s derriere as they performed an x-rated semi-tango.

But the odd thing was that after all this effort, there appeared to be no chemistry between the pair – in fact, if you didn’t know they were sleeping together, you’d never guess.

It was a stark contrast to J-Lo’s performance with estranged husband Marc Anthony at last year’s Idol finale, which was sparking with electricity.

So if it was intended to send a message to her ex, it wound up being the wrong one.

Isn’t he cute? Odd description to give a lover 17 years your junior

Support: Casper was right behind his lady at all times as she sang her ode to new beginnings and er, dancing again…

The worst moment came in a clearly staged moment that saw Casper pick confetti out of J-Lo’s hair after the performance ended in a flurry of ticker tape.

She immediately said to the audience: ‘He’s so cute!’

You’d really think the Bennifer disaster would have taught her a lesson.

Lopez was never more unpopular or lampooned than in the aftermath of her nauseating 2002 video for Jenny from the Block which co-starred her then boyfriend Ben Affleck.

Finale: The ticker tape rains down and J-Lo, Casper et al look pretty pleased with themselves

Grooming his mate: Casper reaches into J-Lo’s hair for the rogue piece of confetti

The pair were shown cavorting on a yacht, with the Academy Award winning actor nuzzling into J-Lo’s bikini clad body and untying the hot pink top.

Now married to Jennifer Garner with three little ones, Affleck – who was engaged to marry the Latino singer – says he regrets doing the video.

And you’d think that maybe Lopez would too, but on the basis of this performance – and indeed the video Dance Again, apparently not.

Busy bee: Jennifer celebrated the launch of her new scent Glowing by JLo at Hotel Bel Air, left, and right, seen on set at American Idol