David Luiz has experience indifferent fortunes since his arrival at Stamford Bridge.
Initially advertised to the Chelsea faithful as an exotic centre-back who could distribute and defend in equal measures, he endured a dismal start to life in west London, before seeing his form pick up over the course of last season.
In my opinion however Luiz remains a ticking time bomb in most of Chelsea's fixtures, and in complete contrast to claims that the armband beckons in the near future at Stamford Bridge, I think he needs to go.
Whilst extremely effective going forward, Luiz is simply not cut out to serve as a centre-back under Jose Mourinho. The Special One historically fields resilient pairings at the heart of his defence, and put simply he prefers defenders who like to defend. Luiz most certainly doesn't fit that bill.
In the Premier League in particular, defenders have to be able to remain positionally aware and tactically astute. Whilst Luiz can lay claim to exceptional ability in terms of literal footballing skill, his concentration and application to the job at hand when put in defence leaves much to be desired.
The lung-busting marauding runs the Brazilian has become infamous for are tailor made for someone playing three or four positions further up the pitch, and when Luiz is deployed in a centre-midfield role it really does add an extra element to Chelsea's attack. However when the 26-year-old is supposed to be serving as part of a four-man unit designed to keep out goals, his outlandish surges forward and general disregard for staying tight to the opposition leaves his side dangerously exposed.
A perfect point in case would be Chelsea's weekend loss to Everton. When Stephen Naismith's header put the Toffees a goal to the good, Luiz was to be found standing on the edge of his own box the wrong side of four Everton players who had made their way into attacking positions.
The former Benfica man may be a gifted footballer, but he's simply not suited to defending in the Premier League, and when it's considered that that's his area of speciality, one can really start to pose a question as to how effective he can realistically be at Chelsea.
No matter which way you look at it there doesn't seem to be a place for Luiz. Around six or seven creative players already vying for starting positions in Chelsea's midfield, and although talented going forward for a centre-back, he's not going to challenge Mata and co. for a place behind the strikers.
Currently carrying a price-tag of almost £40million, it's a wonder that the Blues didn't part way with him in the summer. Barcelona appear to be the most viable of destinations and had previously declared strong interest.
Luiz at Barca makes for a much more practical outlook.
The emphasis at the Catalan club, for the meantime anyway, is set around every player on the pitch being able to distribute passes and make runs into space; traits that Luiz has shown time and again in the Premier League.
Whilst Barca focus on being so attack-orientated that their back line's primary function shifts from defending to providing support going forward, Chelsea rely on solid positional structure, negating Luiz's strengths.
For me Chelsea should part ways with their roaming centre-back in January whilst his valuation is still high. In Gary Cahill and John Terry Mourinho has the two old-fashioned centre-backs he needs to do the job until the end of the season, and the money they would make from Luiz's transfer would almost certainly guarantee them a more assured centre-half.
Luiz is good, but not Mourinho's cup of tea. Far more suited to continental football, the Brazilian just isn't capable of performing in the Premier League whilst being restricted to defensive lines.
Barca beckons, and Mourinho should oblige.