From the minute that Taylor Swift and Harry Styles began doing the horizontal tango publicly dating, One Direction fans had one main concern - that the songstress would slag him off in song when they broke up.

However, some sources suggest that Harry and Taylor started dating before Swizzle's relationship with Conor Kennedy - and before she'd finished writing her latest album, Red. D'you see where we're going with this?

Taylor Swift holds Harry Styles hand as he gets new boat tattoo in LA - PICS

Yep, #HaylorSongLyrics was trending worldwide yesterday, with some (hilarious) ideas for possible break up song titles being bandied about by Twitter users.

But it seems Swifty could have beaten them to it, and snuck in a song about the 1D star on her latest album, Red.

We refer, of course, to 'I Knew You Were Trouble'. Let's examine the evidence shall we?

1. Taylor was said to have been left 'heartbroken' by Harry after the pair hooked up when One Direction were touring America in early 2012 - only for him to be pictured snogging model Emma Ostilly weeks later. This coincides rather nicely with the time that Tay was writing Red. Dun Dun Daaaa.

HARRY STYLES AND TAYLOR SWIFT

2. Swifty has been known to hide 'hidden messages' inside her album booklet. The message written next to I Knew You Were Trouble reads 'When you saw me dancing'. Could this be a reference to that time Tay-Tay was seen bopping around to 1D at the 2012 Kids' Choice Awards? COULD IT?

3. A source claiming to be 'close to the situation' told Hollywoodlife.com “The song ‘Trouble’ is definitely about Harry. Taylor told Harry it’s about him. She references flying around America following One Direction’s tour.”

4. Most convincing of all is a tweet sent by Taylor after she and Hazlan supposedly had an 'explosive row' and broke up while on holiday last week.

Taylor Swift and Harry Styles from One Direction break up after almighty row in the Caribbean?

'...'til you put me down.' she wrote. Which is, as we all know, a LINE FROM THE SONG referring to a break up. 

Gahd we feel like Sherlock bladdy Holmes. What do you reckon to all this?

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