Roberto Mancini understands the importance of tightening up defensively if Manchester City are going to win the Premier League this season and the signing of Thiago Silva could represent the final piece of their title-winning jigsaw.
Things have improved of late with clean sheets in the victories over Arsenal and Stoke, although they went nine Premier League games without shutting out the opposition prior to this.
Joleon Lescott has partnered captain Vincent Kompany for the majority of the campaign, although Kolo Toure has been pushing for a recall of late.
There are certainly grounds to believe that Mancini is not 100 per cent sure either are the best partner for Kompany and a new signing would be the overall best solution.
A new defender could also be critical with Toure heading off to the African Cup of Nations in January and Stefan Savic looking increasingly likely to join Sportling Lisbon on loan to increase his first-team opportunities.
Meanwhile, Nedum Onuoha is regarded as one of the players surplus to requirements at Mancini, with the club looking to sell a handful of players so they can buy to fit in with financial fair play regulations.
With Silva expected to cost around £30m from AC Milan, Carlos Tevez could hold the key to whether any such deal could be completed.
Onuoha and Wayne Bridge are the other two players linked with moves away, but Tevez is the only one of the trio likely to bring in any sort of substantial transfer fee.
AC Milan are also one of the teams most heavily linked with Tevez and there is the small chance that the two clubs could agree to a swap deal of some kind for the South American duo.
If Manchester City do manage to bring in Silva, their Premier League odds to win the title would surely shorten.