Why Chelsea Must Ensure Branislav Ivanovic Doesn't Defect to PSG

The winter transfer window has't long been closed, yet rumors of high-profile moves ahead of the summer are already circling.

The latest at Stamford Bridge involves French champions Paris Saint-Germain chasing Chelsea's Branislav Ivanovic.

The Daily Mail reports Chelsea and the player are eager to discuss an extension to his existing deal that expires in 2016, and from the club's perspective, it's a wise move if it means fending off interest.

Forgetting what Ivanovic offers Jose Mourinho's side for a moment, allowing the Serbian to leave doesn't quite stack up up financially, either.

Indeed, Chelsea have shown in the last window the direction their transfer policy is going to take in the coming years as Financial Fair Play rules take hold.

The sale of Juan Mata to Manchester United was a bitter pill to swallow for some, yet at £37.1 million, the Spaniard's departure has helped balance the books.

Add to that the £17 million Chelsea recouped on Kevin De Bruyne's move to Wolfsburg and Chelsea ended January uncharacteristically in the black—and that's despite spending a combined £43 million on recruiting Nemanja Matic, Mohamed Salah and Kurt Zouma.

What those transfers allowed Chelsea to achieve was a balance to their squad.

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For much of 2013-14, defensive midfield represented a significant concern with the absence a truly world-class player to sit in the hole and shield the Blues' defence. Now they have one.

Further forward, Mourinho had an embarrassment of riches with attacking midfield congested by a talented crop of stars. In allowing Mata and De Bruyne to leave, the Portuguese lost two of the weakest players for his system, adding a trio more suited to his and the squad's needs.

It wasn't about individual talent—they were transfers with the collective in mind and the financial implications played their part, also.

With Mata and De Bruyne gone, Chelsea look all the stronger.

Were Ivanovic to depart, that wouldn't necessarily be the case. The Serbian may be talented, but his profile dictates his fee would be considerably less than those commanded by his former teammates and as such, the wisdom doesn't carry.

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Players of Ivanovic's ilk are vital, but clubs do not pay a premium for them like they would a Mata, meaning it would be difficult for Chelsea to replicate the positives from their January transfer dealings.

Then there are the implications on the pitch, where it matters most.

There aren't many better defenders in his position right now and Chelsea have no need to sell Ivanovic. 

With any player, deficiencies will always appear—he's weak here, needs to improve there—yet for his overall game, Ivanovic is ideal for Mourinho's Chelsea. He's aggressive, physical and is comfortable enough in possession to assist going forward. As the recent victory over Manchester City outlined, he can be a match-winner at times, also.

PSG know what they would be getting with the capture of Ivanovic. It's why they're interest in him refuses to abate.

Garry Hayes is Bleacher Report's lead Chelsea correspondent and will be following the club from a London base throughout the 2013-14 season. Follow him on Twitter here @garryhayes