Swansea City made serious error of judgment with £3.5m transfer deal: View | OneFootball

The Frenchman's move to Wales simply did not work out, which proved costly for the Swans

When the 2015 summer transfer window opened, one of the priorities for Swansea City was undoubtedly a new left-back.

While the club did have the ever reliable Neil Taylor as their first choice in that position, behind him, they were lacking in depth on that side of their defence.

Having signed the previous summer from Scottish Championship side Falkirk, Stephen Kingsley had not made a single appearance for the Swans during the 2014/15 season.

Indeed, he had even spent the latter part of that campaign out on loan with Yeovil Town, as they suffered relegation to League Two.

As a result, it did look as though Swansea needed a left-back with more top-flight pedigree to provide cover and competition for Taylor. The man they got to fill that role was Franck Tabanou.

Swansea City spent big on Saint-Etienne full-back

In June 2015, the Swans announced that they had completed the signing of Tabanou, from French side Saint-Etienne.

It was reported that they had paid a fee in the region of £3.5million to complete the signing of the left-back from the Ligue 1 club.

Having made that move, Tabanou put pen to paper on a three-year contract that secured his future in Wales until the end of the 2017/18 season.

Prior to joining Swansea in the Premier League, the Frenchman had spent the whole of his career in the French top-flight, making over 200 Ligue 1 appearances for Toulouse and Saint-Etienne.

That, combined with the fact that he was also versatile enough to play in midfield if required, meant this looked like an exciting signing for the club.

In the end, though, this deal would turn out to be little more than a very costly error for the Swans.

Franck Tabanou never made an impact in the Premier League

Having completed his move to the Welsh club, Tabanou ultimately failed to get into the side when it came to Premier League action.

In his first half-a-season with Swansea, the left-back made just three appearances for the club, all of which came in the cup competitions.

As a result, the 2016 January transfer window saw Tabanou make a swift return to Saint-Etienne, signing on loan for the Ligue 1 side until the end of the season.

The left-back did not hold with his views on Swansea after completing his temporary move back to France.

In an interview, he claimed that he did not understand why the club had not given him a chance in the Premier League.

Tabanou also suggested the club were in a "terrible situation" and that tactically they were "not at the top".

At the time of his departure, Swansea had just climbed out of the Premier League relegation zone with a 1-0 win over Watford.

That win came on the same day they announced Francisco Guidolin as their new manager, replacing Garry Monk, who had been sacked more than a month earlier.

While Tabanou made 14 appearances for Saint-Etienne during his loan spell there, Swansea rallied under Guidolin, finishing a comfortable 12th in the final Premier League table.

Unsurprisingly though, the left-back was not re-integrated into the Swans' squad after his spell on loan with Saint-Etienne.

He was again loaned out in the summer of 2016, this time heading to La Liga side Granada, in a deal that did not go well either.

The left-back made just seven appearances in all competitions during his time there, as Granada finished bottom of the Spanish top-flight, 15 points from safety.

It was at that point Tabanou's ill-fated spell with Swansea would come to an end, being released by the club in the summer of 2017, despite the fact he still had a year to go on his contract.

Consequently, as well as getting nothing from him on the pitch in the Premier League, they received no financial return on their investment in him either.

With that in mind, it is hard to argue against any suggestion that Tabanou surely has to go down as one of the worst signings in the recent history of Swansea City.