Evan Agostini / Invision/AP 1 / 7
Evan Agostini / Invision/AP 1 / 7

Maybe Jude Law and Sienna Miller should take a deep breath before embarking on their rumored summer sprint down the aisle. The London Daily Mail claims the reconnected couple had a public spat this week while partying and playing snooker (think pool, only more complicated) at a private London club.

"They had this blazing row in front of everyone, and Sienna walked out," a source alleges to the tab. "I couldn't tell you what the row was about, but Sienna had a huge tantrum. It was quite dramatic."

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But did the actor, 37, find a way to keep himself occupied while the starlet, 28, seemingly cooled down elsewhere?

"As soon as she left, Jude started blatantly chatting up another girl in the club at the bar," maintains the bystander. "She was very pretty and was clearly delighted that this huge movie star was making a move on her."

(Geez, doesn't she realize that such attention can end in bulk purchases of Huggies?)

Anyhoo, Sienna, who gazed adoringly at Jude when they made their post-reunion debut at the Met gala in New York earlier this month, eventually returned and soon caught sight of the tête-à-tête, says the paper.

"You should have seen her face when she saw Jude and this other girl," head-shakes the mole.

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But neither the squabble nor Law's confab looks to have spoiled their evening.

"It was extraordinary," marvels the snitch. "By the time I left, they seemed to have made up."

Reps for the stars did not respond to our request for comment on the purported dustup, although a source close to Sienna tells us there's no truth to the tale.

Still, their supposedly speedy conflict resolution isn't too surprising. After all, the pair has had plenty of practice.

We recall another public blowup from way back in October 2005, after Jude had diddled the nanny and Sienna called off their engagement but before they officially parted ways.

The argument reportedly took place at a Paris restaurant the day after Law was spotted at a club with Salma Hayek.

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"It was astonishing. Sienna was screaming as she flew into the room," said an eyewitness at the time, "but Jude appeared completely calm and nonchalant."

And just like the latest alleged tiff, it ended quickly.

"Her face was absolutely puce and she was clearly very upset," continued the spy. "But Jude was very calm and within moments Sienna seemed contrite."

Now, five years later, they appear to be right back where they started.

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