Transfer window to slam in Roberto Mancini's face as Bayern Munich close in on Manchester City 'target' Javi Martinez

No marquee signing in sight at Eastlands with Scott Sinclair set to be the last arrival of August

Bilbao centre-half Javi Martinez looks destined to move to Bayern now (Getty Images)

Manchester City are in danger of ending the transfer window period without making the marquee signing their manager has demanded.

The arrival of the winger Scott Sinclair from Swansea today will be only the second major transfer the club has completed since bringing the Premier League title to Eastlands.

In the wake of Sunday's 2-2 draw at Liverpool, Roberto Mancini argued that the final week of the window would go a long way to determining how City defend their title.

However, it seems likely they will miss out on their most important target, Javi Martinez, who is likely to go to Munich rather than Manchester.

As a centre-half who can also play as a holding midfielder, the 23-year-old would fill a significant gap at the Etihad. However, Bayern Munich have declared themselves willing to pay the full €40m (£32m) buy-out clause of Martinez's Athletic Bilbao contract.

The Bayern chairman, Karl-Heinz Rummenigge, said: "We are working creatively and intelligently to settle this and we will work until the final day of the transfer window to get this done."

Like other members of the European financial elite, Manchester City seem to have accepted a while ago that Napoli would not be selling Edinson Cavani. The Uruguayan striker is on the point of accepting a four-year deal, with a €55m buy-out clause, to remain at the Stadio San Paolo.

The Fiorentina striker, Stevan Jovetic, is available for €30m but the club president, Andrea delle Valle, said that they are reluctant to do business now that the Serie A season has begun, especially since the 22-year-old scored twice in their opening fixture against Udinese.

Had Manchester City managed to sign Martinez – and their financial muscle still gives them a slight chance – it might have signalled the beginning of the end for Nigel de Jong at Eastlands. The midfielder agreed with Mancini's assessment that the champions were "not playing at 100 per cent for various reasons".

That is particularly true defensively, emphasised by the fact that Mancini had to employ Pablo Zabaleta, who is not a natural centre-half, in a back three at Anfield. There, for the third successive league game, they were forced to overturn a 2-1 deficit.

"We have to sort some small things out and keep improving because it is not going to be easy," said De Jong. "Wherever we go, people are going to want to beat the champions so we have to stand tall with each other and improve.

"Falling behind is becoming a bad habit and I don't know why it is. We picked it up in the final game of last season against Queen's Park Rangers and we have continued with it in the first two league games. We must improve and show we are up to the test wherever we go. There are enough qualities in this squad."

It is a squad that still requires trimming. If it came as a surprise that Mancini was prepared let his first signing, Adam Johnson, leave for Sunderland, it is astonishing that Roque Santa Cruz, who has started six league games for Manchester City in three years, is still at the Etihad Stadium.

That may change if either Malaga or Real Betis can come up with around £3m for the 32-year-old, which emphasises the enormous cost of breaking up the strike force Mancini inherited from Mark Hughes. Manchester City paid £106.5m for Jo, Robinho, Emmanuel Adebayor, Santa Cruz and Craig Bellamy.

Once the Santa Cruz deal is done, all will have been disposed of, at a loss, not including wages, of more than £70m. That alone might explain why City are rather more cautious in the transfer market than they once were.