The transfer deadline is just four days away, and Chelsea have already made a big splash in the final week with the official announcement of two prominent additions to their squad as striker Samuel Eto’o and attacking midfielder Willian have left Anzhi Makhachkala for Stamford Bridge. More deals could be on the way for Chelsea, as a few other prominent names have been linked to recent speculation.

Eto’o joins the Blues on a one-year deal and on a free transfer after just two seasons in Russia. Even at the age of 32, the Cameroonian could still perform a key role for new manager Jose Mourinho, who he played for when they were both at Inter Milan.

"It wasn't a hard decision. I saw the qualities Chelsea have, and I was very happy with Jose Mourinho before, so when the opportunity came, I was very happy to take it," Eto'o told Chelsea’s official website.

"I am very happy to be here but also anxious because I want to get playing as soon as possible."

Willian, who cost £30 million and signed a five-year deal, has greater long-term prospects, but the 25-year-old Brazilian faces much competition from Chelsea’s already envy-inspiring list of attacking midfielders.   

“I'm very happy to be here, it's been a dream of mine to come and play here,” Willian said. “Chelsea are one of the best clubs in the world, and now I'm going to play for one of the best managers in the world, so I'm very happy and looking forward to it.”

That may not be the end of Chelsea’s summer business, though, with the Daily Mail reporting that Chelsea are looking to complete a £3.5 million deal for Porto winger Christian Atsu by Friday.  The 21-year-old Ghana international, who came through the youth ranks at Porto, has also garnered interest from Liverpool, Tottenham, Everton, and Sunderland in recent months.

With all the talk of players on their way to Stamford Bridge, there have also been rumors of two notable players on their way out. With Eto’o’s arrival giving Mourinho four strikers, Chelsea would doubtless like to move one of them on. Given the potential of Romelu Lukaku and that Fernando Torres’ hefty salary makes him hard to shift, Demba Ba looks the likely option to being heading for a quick exit.

Indeed, a return to the club which he joined Chelsea from just seven months ago, Newcastle United, could be on the cards, according to Sky Sports. The Independent reported that Ba could move back to St. James’ Park on a loan deal.

Ba was not in the squad for Chelsea’s match with Manchester United on Monday, and didn’t see action in the season opener against Hull City.

While Ba’s return to Newcastle appears plausible, the same can’t be said for the potential departure of David Luiz. The Daily Mirror made the surprising claim earlier this week that Manchester United are interested in adding the Brazil international on a £30 million fee. Barcelona made an approach earlier in the summer, with reports that David Luiz’s flamboyant style wasn’t a match with Mourinho’s more regiment ideas about the game.

But the 26-year-old has ironed out some of his early impulsiveness and Mourinho has previously stated that there was “no chance” Luiz would leave the club as interest from the Catalans was seen off.

"I have known of David Luiz from the very beginning so I know him very, very well,” Mourinho told The Sun. "And before I came back to Chelsea, I watched him week after week.

"I see him as a center-back because he has an important quality for a footballer - he can build from the back. He is very comfortable and confident with using the ball from the back -- he does not play direct. And he can improve, especially defensively. He can be much more effective, much more solid. But the potential he has is amazing, incredible."