This article forms part of our Total Duds feature series, which is where Football Transfer Tavern takes a look at how a player has fared since being signed or sold, using statistical figures and statements from pundits to prove how bad a deal the club got.

Marouane Fellaini split opinions right from the start and his arrival at Old Trafford spelled almost certain doom for Manchester United.

Fellaini moved to United from Everton for £27.5m at the end of the deadline day, reuniting with his old boss David Moyes, who had succeeded Sir Alex Ferguson at the helm. Moyes had previously brought the player to Goodison Park from Standard Liege in September 2008.

Ever since the Belgian arrived at Old Trafford, the Red Devils have failed to win the league after Fergie's retirement, and the closest they have come is a second place finish behind derby rivals Manchester City at the end of the 2017/18 season.

After missing out on Gareth Bale to Real Madrid, the club redirected their attentions to Cesc Fabregas and Toni Kroos, but ended up with Fellaini instead. Moreover, the former Toffees star was the only new signing to join in the transfer window. It is well worth considering how United's fortunes might have been different had Fabregas joined the side, as the Spaniard went on to help Chelsea win two Premier League titles.

Perhaps unfairly, the midfielder also had big boots to fill almost immediately, as club legend Paul Scholes retired in the summer.

First, he had to compete for a place in the starting lineup with Tom Cleverley, surprisingly losing out to his teammate as the Englishman went on to make 30 appearances under the Scotsman in all competitions.

Although Fellaini finished his first season at the Theatre of Dreams with a fairly high rating of 7.21 for his performances in the English top flight, this was a decrease in value from the campaign beforehand, and things had begun to unravel in the Champions League.

He was infamously sent off in the dull 0-0 draw with Real Sociedad in the group stages, picking up his first red card for the club in the process (ESPN).

In April 2014, he was even named as one of the '10 Worst Buys of the 2013-2014 season' by the Daily Telegraph, as he failed to score a single goal in the Premier League.

Moyes was unceremoniously sacked by the board after an abysmal stint in charge, and the Scottish manager was replaced by Louis van Gaal. LVG tried to play Fellaini as a striker, but, by that stage, the damage had already been done. Besides, lumping the ball forward has never been the United way (BBC).

Despite the fact he became Jose Mourinho's main man, the veteran copped a fair amount of criticism, as he didn't fit the traditional attack-minded profile that befits a Manchester United player.

Indeed, his best position was arguably in the number 10 role during his time at Everton, mostly due to his physicality in attack and defence, but he spent the majority of his time at United in the centre of the pitch. Shockingly, Fellaini scored just 22 goals and created only 12 assists in over 177 appearances for the Manchester club.

His steady decline in form can be reflected by his market value, which dropped from £25.2m in July 2013 with the Blues, to £13.5m by the time he left Old Trafford. He finished his career in England with a low overall rating of 6.66 via WhoScored.

While it might seem unfair to pin the blame for United's struggles in recent years entirely on Fellaini, the expensive signing turned out to be quite a major flop, and the Red Devils finally sold him for just £6.48m to Shandong Luneng Taishan, well short of the initial fee they paid the Merseyside club.

Therefore, Moyes' failure to land a top transfer target led to his inevitable downfall, and buying the former Belgium international turned out to be one of his biggest mistakes.

United fans, do you think Marouane Fellaini is the worst signing in the club's history? Let us know down below!