Harley Mills could be ideal KT understudy if Peterborough’s price is right

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The Celtic Star

·5 Juni 2025

Harley Mills could be ideal KT understudy if Peterborough’s price is right

So, having looked at Moroccan striker Youssef El Kachati and 19 year old Japanese full back Keita Kosugi earlier on The Celtic Star, we’re also going to have a look at another left back linked to Celtic in the close season, as the club’s recruitment team look to strengthen Brendan Rodgers squad ahead of a title defence and another tilt at Champions League football.

Harley Mills of Peterborough United celebrates scoring his team’s first goal during the Vertu EFL Trophy Final match between Birmingham City and Peterborough United at Wembley Stadium on April 13, 2025 in London, England. (Photo by Richard Pelham/Getty Images)

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Before I delve into Peterborough United left back Harley Mills, I would just like to put out a disclaimer.

If at any point, we end up ‘in the know’, and we can publish a transfer target, we’ll do so and will be happy to tell you all about it. In the meantime please assume the players we are looking at are players Celtic have been linked with in the press, or from a multitude of other places, and are talents we think may be a good fit, sounds like a reasonable player, or within our budget but also are realistic options taking into account the squad make-up.

We haven’t made them up (although others may have!) or if they sound ludicrous off the bat, we won’t even tell you.

For instance, I got a message a couple of days ago saying Manchester City had offered Vitor Reis to Celtic on loan basis, and that Celtic had been recommended to the player by City. However, given he’s only played one game for Manchester City since signing for £37m from Palmeiras less than 6 months ago, and is probably on wages the equivalent to half of Celtic’s entire weekly wage bill, it’s safe to say it didn’t have me wanting to put it out as an article.

However, the free transfer of Youssef El Kachati, a 25-year-old who has played lower leagues in the Netherlands seemed a bit closer to our ballpark!

So, back to the young left back who sounds like a high end Lambswool supplier!

First, let’s get his dead ball abilities out of the way with a peek at this strike for Peterborough United against Birmingham City. It’s a good start and draws you in immediately, particularly when it may well be possible the last direct free kick scored by Celtic came in the Bernabeu from the feet of Jota… in his first spell at the club. Shudder!

I must admit, that strike aside, it may also be worth considering left footed inswingers from young Harley on one side and the excellent Arne Engels on the other, might also see Celtic score from corner kicks next season too. Okay, took that one too far perhaps – a bhoy can dream.

Harvey Mills is a 19-year-old attacking left back, who has very occasionally also played as a left sided midfielder, it’s no surprise then that he is left footed and has a decent level of pace to call on.

The youngster started out at Aston Villa but didn’t trouble the first team before moving to Peterborough United in 2024. Mills then had an eight-game loan spell with Enfield Town before replacing Harrison Burrows as The Posh’s first choice left back and playing 1822 minutes over the course of 25 games with Peterborough scoring two goals and assisting a further two more.

Now he has had interest from elsewhere and it seems Peterborough are aware of Celtic interest but have advised they’ve had no direct contact from the club regarding a transfer so far.

The other interest seems to be coming from Fulham, and it’s said a £1m bid was made very recently.

That would normally have put me off, after all with the money swirling around the EPL there is often little point in Celtic engaging. However, it seems Fulham see Mills as a prospect for the future and their intention had not been to add him to the first team squad but instead add him to their Under 23 squad for next season.

With Celtic looking for cover for Kieran Tierney – assuming Greg Taylor doesn’t surprise us all by signing a new contract – then Mills could find himself getting significant gametime at Celtic and as such may well be more attractive than an EPL side on this occasion.

Harley Mills of Peterborough United poses for a photo with the Vertu EFL Trophy following the team’s victory during the Vertu EFL Trophy Final match between Birmingham City and Peterborough United at Wembley Stadium on April 13, 2025 in London, England. (Photo by Richard Pelham/Getty Images)

Mills scores well statistically when it comes to dribble successes 66.7%, duels won, 62.4% and aerial duels won 56.7%, with bodes well for an offensive left back but he scores low on crossing accuracy 20.6% and long passes accuracy 28%.

To be fair, young Mills has only got into Peterborough’s team last season and even then, only became a regular towards the end of the campaign so the sample size on which to judge is quite low.

We also have to take into consideration, whilst League 1 in England probably equates to a similar standard as the Scottish Premiership outside the top 3, it is still hard to judge if the step up to Celtic may be a big leap – however we don’t need reminding of Ivan Toney do we?

Having looked at Keita Kosugi earlier on The Celtic Star, it’s safe to say the Japanese player looks the better prospect, but it should be noted he’s played more football than Mills and he’s been exposed also to European football, something Harley Mills has not. He’s also valued higher at £4m, while Mills is expected to move on for around a quarter of that fee.

Celtic goalkeeper Viljami Sinisalo applauds the fans at full-time. Final score Celtic 5 Kilmarnock 1. Celtic v Kilmarnock, Scottish Premiership, Celtic Park, 12 April 2025 Photo Stuart Wallace/Shutterstock

All that said when Celtic signed Viljami Sinisalo, we may have signed him from Aston Villa (where Mills too began his career) but he was just off the back of a successful season with Exeter City, so there are certainly parallels with this rumoured target.

It would take a bit of a leap of faith to say this is a bona fide Celtic target, but with Paul Tisdale involved in talent recommendations these days, the lower two divisions of England is certainly his manor. Add to that, David Pleat we know is also looking in that market on behalf of Celtic in a consultancy basis.

As far as back-up full backs go, I wouldn’t be surprised if there is genuine interest from Celtic in Harley Mills, it certainly seems to fit, and it would also be a player patient enough to play a support role to Kieran Tierney as he learns the ropes.

The downside is having to negotiate with Peterborough United, although they would probably say the same things about us after the Ivan Toney fiasco.

Niall J