A little less than a year ago, Chris Smalling was a marked man in the red circles of Manchester. The England centre-half was sent off in Louis van Gaal's first Manchester Derby at the Etihad Stadium when he upended James Milner needlessly and recklessly, earning himself a second yellow after just 39 minutes.
From that point on, City dominated - and duly picked up three points thanks to Sergio Aguero's winner.
Van Gaal pulled no punches in his post-match assessments: "The second yellow card was stupid. You cannot do what he has done with the second yellow card. That is not very smart. What can I say?"
It may have only been one game, but it was a huge moment for Smalling. Four years after Sir Alex Ferguson signed the highly-rated youngster from Fulham, there was still serious conservation over Smalling's merits as a future rock in the United defence. The jury was well and truly out.
Since then, however, Smalling has transformed. He's harnessed his aggression into making him one of the most ferocious, yet controlled defenders in the league. So far this season, he has been Van Gaal's outstanding player - just as David de Gea was last season. While the Dutchman has experimented - with mixed results - in deploying Daley Blind as some form of playmaking centre-half, Smalling has been the solidifying element. The reason for showering praise on him comes not from one or two eye-catching displays, it comes from effectively being United's best player since the turn of the year.
In United's impressive 3-0 win away at Goodison Park - the stage which saw a crushing 3-0 reverse last season - Smalling thrived with Phil Jones alongside him, reigniting an out-and-out central defensive partnership that never quite got going while the two players have been at the club together. Finally, it looked like Ferguson's vision had been realised. Jones and Smalling together at the back, suppressing the threat of Romelu Lukaku and ensuring United got their campaign back on track with a clean sheet and three much needed points after the bruising defeat to Arsenal.
Fears over Blind's capabilities as a centre-half were fully realised in United's two defeats this season. Against Swansea, he was targeted by the imposing physique of Bafetimbi Gomis and struggled badly. Then, against Arsenal, the Gunners sought to isolate the Dutchman against speedy attackers like Theo Walcott with regularity. It worked. Blind looked lost at sea at the Emirates and it has ultimately cost him his place in the starting line-up for now.
For Smalling, however, he faces his toughest challenge yet in leading the United defence against a rampant, goal-happy Manchester City that has plundered 11 goals in their last two Premier League outings against Bournemouth and Newcastle United. City may not have the creative guile of David Silva or the sheer predatory nous of Sergio Aguero, but what last week proved was that City can still thrive without their extravagantly gifted attacking axis.
Raheem Sterling's pace is always a problem, but it looks like he has recaptured an ability to finish, while Wilfried Bony finally ended a period of torment in front of goal with a brace against the Cherries. What does that mean? That Smalling will have to be at his best in the face of Manuel Pellegrini's frighteningly trigger-happy side. Kevin De Bruyne too, has hit the ground running since his high-profile summer arrival and only adds further significant firepower to City's artillery.
Smalling has historically struggled on some big occasions, but at 25, it finally looks as though he has developed a leadership mentality for Van Gaal. Unlike this time a year ago, he can be entrusted with the responsibility of stopping United's bitter rivals and in a game that could wrestle the momentum away from the Blue half of Manchester once again and send the Red Devils to the Premier League's summit.
It takes all good defenders time to evolve and cement that sense of maturity that is essential for the rigours of the elite game. Smalling looks as though he has found it.
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