Chelsea's purported interest in Napoli central defender Kalidou Koulibaly has reportedly been in the pipeline for weeks, and over the last few days that interest was made concrete.

Numerous media outlets, including this article by Sky Sports, have confirmed that Chelsea have bid for the 25-year-old defender, with a fee around £38million being discussed.

Now, Koulibaly is a very good defender - there is no doubting that; but £38 million is a lot of money for a defender that has for the most part had one good season.

Prior to the 2015/16 season, he looked very average for Napoli; and so it could be seen as a risk to invest so much in a relatively unproven player.

Instead, could Chelsea's cash be served better by placing their attention on another defensive target?

Here are FIVE alternatives for Chelsea as opposed to signing Kalidou Koulibaly...

Nikola Maksimovic

One player that Chelsea ARE reportedly looking at as an alternative to Koulibaly is Torino central defender Nikola Maksimovic.

The defender played 16 games in Serie A last season in a Torino side that finished 12th in the league.

Numerous media outlets are reporting on the interest, with The Mirror suggesting that The Blues see the Torino defender as a cut-price alternative to Koulibaly.

Interestingly, Di Marzio has since discussed that both Napoli AND Chelsea are in for the player, with Napoli looking at him as a potential replacement for Koulibaly.

The £15-20million fee's being banded around are certainly a far cry from the near £40million interest that Chelsea have in Koulibaly; so if the club have faith that the cheaper defender is good enough to succeed at the Bridge - this one does make sense.

Stefan De Vrij

Another player that the club are reportedly looking at is Dutch defender Stefan De Vrij.

Like Maksimovic, De Vrij is seen as a cut price alternative to Koulibaly, with The Daily Express putting the deal at around the £15million mark.

De Vrij would represent more of a risk than the other two; given that he suffered with a host of injury problems last season. But Chelsea clearly see themselves fit to solve De Vrij's issues with the excellent facilities available at the club.

Both transfers represent huge risk to the club...perhaps they should instead go for more of a long-term target?

John Stones

Chelsea's interest in John Stones has been long discussed, with the club having a number of big money bids rejected for the young defender last summer when Jose Mourinho was in charge.

It seems unlikely that the interest would have disappeared in that time, with the club likely feeling instead that they were priced out of the move.

In reality however, the £40million reportedly touted for a Koulibaly move would likely not be much less than Everton would command for a player like Stones.

A move for Stones would undoubtedly make more sense; homegrown talent in of itself is hard to find, and Stone's quality is clear for all to see.

Like Koulibaly, Stones has been inconsistent during his career - but if there is anyone able to bring the best out of a player defensively it is Antonio Conte.

Unfortunately, the going rate for central defenders is huge at the moment...maybe the club should look a little closer to home?

Matt Miazga

Matt Miazga signed for Chelsea for nearly £5 million at the start of 2016; and the deal seemed to make little sense.

Very little was known about the young American defender, and since joining the club he has received almost no game time.

If Chelsea are however cautious about spending big money on central defenders; perhaps Miazga could prove to be a solution?

The club obviously saw something in him, otherwise  he would not have been signed - so it would make sense to utilise him.

The club would surely only sign players if they are good enough - so maybe Miazga needs to be given a real chance?

Jake-Clarke Salter

Alternatively, if Conte doesn't see Miazga as a future Chelsea star - perhaps he should look even lower in the pecking order.

Jake Clarke-Salter is seen as the best central defender in Chelsea's developmental system; and it would make sense to give him an opportunity as well.

Eyebrows were raised by players and fans alike following the signing of Miazga, with many feeling that Clarke-Salter possess more talent than the American.

Ola Aina has come in to the squad during pre-season and has proved that the Chelsea youth teams are good enough for a spot in the first team; what is stopping Clarke-Salter from doing the same?

Again, like Miazga - Chelsea seem to be afraid to spend big money on centre backs this summer - why not utilise what you already have and save a bit of money?