Since joining Chelsea in January 2008, Branislav Ivanovic has shown a steady improvement in quality and understanding of his particular role – until this season. Originally signed for his versatility as a center and right back, the Serbian’s game has evolved to include an attacking prowess now deemed necessary for the modern fullback.

He’s had his ups and downs along the way, struggling to find the scintillating form he exhibited at points during Chelsea’s title-winning season.  However, I think many of his recent struggles can be attributed to being played in multiple positions under four different managers during his first 18 months at Stamford Bridge.

In a period I fondly refer to as “the Troubled Age,” trigger-happy, trophy-hungry Roman Abramovich sacked Avram Grant, then Luiz Felipe Scolari, then brought in Guus Hiddink before finally hiring Carlo Ancelotti, all between the 2007-08 and 2009-10 seasons. Under Grant, Ivanovic never featured, finally making his debut for new manager Scolari in the League Cup against Portsmouth. His next competitive showing lasted all of five minutes, coming off the bench for then-favored José Bosingwa in the 85th minute in a 3-0 victory at Hull City’s KC Stadium.

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It wasn’t until mid-November of the 2008 season when Ivanovic first started a league match, doing so in place of Alex at center back. Four starts later, he was once again relegated to the bench following a poor performance against Arsenal.

Scolari’s departure and Hiddink’s arrival in February 2009 saw the Serb given very little first-team time, and it took him until April 2010 to break into the team. In the 2010-2011 season, under Ancelotti, Ivanovic featured far more in the starting XI, benefiting from a long-term injury to Bosingwa. It’s worth noting that Ancelotti favored an attacking-style 4-4-2 – a formation at which the Serb excelled in defense, while also making headway in his forays forward. His form that year was so good that he began receiving interest from other clubs, leading to heavy links with Fiorentina and Real Madrid during the 2011 winter transfer window, and culminating in his signing a new contract with the Blues, binding him to the club until 2016.

Still, it was not until the arrival of André Villas-Boas, following the sacking of Carlo Ancelotti in May 2011, that Ivanovic cemented the right back position as his own. Ironically enough, his versatility was his biggest hindrance: having to compete for a center back and right back position prevented him from being a consistent player in either. Under AVB, Ivanovic improved at his favored position but at times was still asked to play center back. Such was also the case under Roberto Di Matteo and Rafa Benitez, and Ivanovic scored important goals for both managers while playing different positions. Chelsea fans will certainly recall his strike as a right back against Napoli at Stamford Bridge which propelled Chelsea to their tournament-winning finish in the 2012 Champions League. The following year, in the 2013 Europa League final, his header as a center back won the competition for the Blues.

It might be easy to forget how vital his performances have been for the Blues in recent seasons when analyzing his current form.  But while he’s been exposed in Chelsea’s first five fixtures this year, the signs were there for much of last season.

Against Swansea City in September of last season, Ivanovic endured a similar dip in form which saw Chelsea punished on the defensive end.  The first goal conceded was a result of his failure to track the outside run of Neil Taylor. Not 10 minutes later, the Serb lost sight of Wayne Routledge — again on his outside — whose curling effort just missed Thibaut Courtois’ far post.  Similarly, last week in Chelsea’s 3-1 loss to Everton, Ivanovic seemed lost.  James Naismith scored two rather preventable goals in the first half which an alert right back would have likely prevented.

Previously known for bullying defenders to the point that they’d prefer to drive infield or simply go backwards, this season Ivanovic has been being consistently beaten around the outside by eager wingers and fullbacks (such as Yannick Bolasie, Aleksandar Kolarov and Andre Ayew, to name a few).  When anticipating a cross or shot, he’s attempted the rather lazy, arms-behind-the-back block, which has yet to be effective and only seems to invite players to fake and dribble past.

Chelsea fans were likely demanding, “Why hasn’t Brana been dropped!?” or, “When will we finally see Azpi (Cesar Azpilicueta) on the right side??” following the Blues’ dismal 3-1 defeat at Everton last weekend.  And they’re right to ask these questions.  It would seem insanity to continue starting Ivanovic when the reigning Premier League champions have arguably the best right back in the league in Azpilicueta, who has (by quality or lack of choice) made the left back position his own.

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José Mourinho, who made scathing criticisms of several players following the home loss to Crystal Palace, has somehow stuck with Ivanovic despite having signed a quality left back in Baba Rahman.  But Rahman, who last night made an energetic start to his Chelsea career, featuring for all 90 minutes in a 4-0 defeat of Maccabi Tel Aviv, might have just forced the Portuguese tactician’s hand.  Azpilicueta, who started in place of Ivanovic, was nothing short of dominant in his favored position.  Rahman’s forays forward and link up play with Eden Hazard showed promise and understanding.  It was an altogether different looking defense Wednesday at Stamford Bridge – one we may see more often in the weeks to come.

Chelsea’s starting back four against Maccabi Tel Aviv could very well be the one which Mourinho uses for the majority of the season.  Perhaps he’s still tweaking it, but Rahman, Gary Cahill, Kurt Zouma and Azpilicueta seem a strong, cohesive group.  It will take time, but the Serb may end up featuring more often at center back.

John Terry (34) and Ivanovic (31) are Chelsea’s most senior players.  They were instrumental in the Blues’ successes last season and for many seasons prior, but perhaps their time has come.  An aging defender on a title-contending team can be a huge help or a massive hindrance.  It appears Ivanovic has become the latter.