Middlesbrough will always wonder 'What if?' after Man United landed £31m star | OneFootball

Boro saw a deal for Benfica's Victor Lindelof collapse multiple times in January 2016, and 18 months later, he'd made a £31m move to Old Trafford.

Championship side Middlesbrough saw multiple deals for Benfica's Victor Lindelof collapse in the January 2016 transfer window, and by June 2017, he'd become Manchester United's most expensive defender of all-time.

Boro, then under the management of Aitor Karanka, were looking to bolster their promotion credentials with some strong signings in the winter window of 2016, and Benfica's Swedish starlet was a player they'd been tracking since he was 16.

At the time of Middlesbrough tabling their interest, Lindelof was on the fringes of the Portuguese side's squad, having made just one senior appearance for the club, as he'd spent the vast majority of his time in Benfica's B team.

As such, Boro felt now was their time to swoop in for a player who had long been on their radar. What unfolded next would become one of Middlesbrough's most frustrating transfer sagas in recent times, and leave the Teessiders with one of their biggest 'What if?' transfer tales...

Boro were left frustrated as numerous factors stopped Lindelof from securing a move to the Riverside

The news of Lindelof's imminent Middlesbrough move was first reported on 13 January 2016, with it being revealed that Boro had agreed a loan deal with Benfica that would see the defender join the club until the end of the season.

That deal also included the option for Boro to make his temporary Teesside switch a permanent one in the summer, which was understood to be just £5m.

However, the first of Middlesbrough's setbacks was about to arrive. As it turned out, Lindelof's agent at the time wasn't FIFA registered, meaning he could broker deals in Portugal, but not international ones. That meant that if the deal was to be completed, the player would need to find a new one to broker the transfer.

This resulted in the deal being put on ice, but after changing who represented him, it was reported to be back on again just a week later on 18 January, with Boro hoping to wrap the move up in the next 24 hours.

Cue setback number two, as Benfica had now decided to move the goalposts over the financial framework of the deal. It was later revealed that the Portuguese club had made fresh demands in relation to add-ons and promotion bonuses, which had left Boro frustrated.

Lindelof then appeared for Benfica in a cup game, after an injury in the starting XI had seen him drafted into the squad, and that only served to slam the door shut on Boro's latest attempts to bring him to the North East.

Karanka and Middlesbrough chairman Steve Gibson were clearly desperate to get the deal done, however. So, after reworking the makeup of the transfer, Boro once again believed they had their man.

It was reported for a third time on 23 January that Lindelof would be moving to the Riverside, but in this case, it wasn't third time lucky for Boro. Like they'd done before, Benfica once again wanted to change the financial aspects of the transfer, and for Middlesbrough, enough was enough.

Jose Mourinho brings Lindelof to Old Trafford in record-breaking deal just 18 months after Boro saga

Boro walked away from their pursuit of Lindelof, and would go on to secure automatic promotion to the Premier League that season.

As for the Swede, the second half of the 2015/16 season would see his long-awaited breakthrough in the Benfica first-team squad materialise, as he went on to make over 20 appearances in the remainder of the campaign.

The following term saw him take his game to another level, as he became an invaluable member of Benfica's starting XI, making 47 appearances in all competitions.

That caught the attention of some top clubs, including Manchester United, who at the time were under the management of legendary boss, José Mourinho.

United would splash out a reported £31m to bring Lindelof to Old Trafford in June 2017, just over a summer removed from potentially sealing a permanent switch to Middlesbrough for a fraction of that.

This made Lindelof Manchester United's most expensive defender of all-time, as the Swede - 22 at the time - would surpass the £29.1m figure that United paid to acquire Rio Ferdinand in 2002.

Lindelof has made Manchester his home ever since, playing a significant role for various United managers, with his versatility and consistently solid performances earning him over 260 appearances for the Red Devils.

He's won an FA Cup and a Carabao Cup during his time with the club, and has also firmly established himself as one of Sweden's best players during his career, having represented them at two Euro 2016 and 2020, as well as the 2018 World Cup.

Had Middlesbrough signed Lindelof for £5m in the summer of 2016, they not only would've secured a top class central defender that would've no doubt boosted their chances of survival in the Premier League for the 2016/17 season, but he could've developed into one of the club's all-time biggest bargains.

It's fair to say that Lindelof won't have any regrets over missing out on a move to Middlesbrough, but for Boro, it's perhaps one that still elicits the odd grumble of frustration from Gibson whenever he sits down to watch the Swede play in a Manchester United shirt.