Chelsea can unleash £60m weapon after brutal chat revealed and controversial transfer decision

Saturday afternoon could be the first time we witness Marc Guiu start a Premier League game for Chelsea and - rather ironically - it could be against Sunderland.

Guiu moved to the Black Cats on August 6 on a season-long deal with Chelsea wanting the striker to get first-team experience under his belt. At the time, the Blues had just signed Liam Delap for £30million and Joao Pedro for a complete package of £60million. Maresca also had Nicolas Jackson on the books and the club were content with their options.

Sources said at the time that Chelsea wanted two out-and-out No.9s and in Delap and Jackson, they had just that. The Blues were also after a versatile forward and in Joao Pedro, they have that; someone who can play across all positions in the attack. In early-August, though, Jackson informed Chelsea that he wanted to explore a move away from the club, with the striker and his representatives well aware of mass interest in his signature.

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Chelsea then decided to leave the Senegal international out of their squad for their opening pre-season clash with Bayer Leverkusen. It took a while - and a whole lot of drama - but Jackson eventually sealed a loan move to Bayern Munich, with the German champions having an obligation, understood to be worth around £70million although the conditions of the clause have not been made public.

Delap suffered a serious hamstring injury that put Jackson's loan move in doubt, but it was eventually completed with Chelsea deciding to go down another route.

The Blues decided to recall Guiu from his loan spell at Sunderland, just 26 days after the Spaniard put pen to paper at the Stadium of Light. Chelsea's decision was widely criticised with the 19-year-old's development on the line. There were no clear signs of Guiu being an option for Maresca, with the Italian often choosing Tyrique George, a left-sided winger naturally, as a false nine.

After being recalled on September 1, Guiu was not used at all by the Chelsea head coach until October 4, when he came on in the second-half in the dramatic victory over Liverpool at Stamford Bridge. As revealed during Friday morning’s press conference, Maresca had taken issue with the way Guiu was training. While not going into the intricate details of why he was not impressed with the Spaniard, Maresca is adamant the problem has now gone after having an honest conversation with the forward.

"We had a chat with Marc two weeks ago," Maresca explained. "I told him that the way he was training, I didn’t like it, and he needs to change. He changes and he got a chance, so it is like that."

When pressed on more detail, the Chelsea head coach replied: "He was not training well."

Supporters were not aware of this, of course, and they were just looking forward to seeing Guiu on the pitch with striker options scarce.

They got their wish against Nottingham Forest. Not from the start, but Maresca called upon Guiu at half-time at the City Ground. With the game goalless when he entered the pitch, Guiu left a really positive impression on the Chelsea head coach as the visitors ended up winning by three goals to nil in Nottingham.

Guiu was then rewarded with a first start for Chelsea's senior side in over 10 months in the Blues' third Champions League fixture of the campaign. The Spaniard opened the scoring as Chelsea dismantled Ajax at Stamford Bridge, and with the Blues three goals to the good at half-time, the striker was taken off - perhaps with an eye on him facing his former club at the weekend.

Sunderland come to SW6 on Saturday afternoon as they look to continue their fine start to the Premier League season. Even without Guiu, Regis Le Bris' men have been the surprise package of the English top-flight thus far.

All of the sudden, with Guiu's recent appearances, Maresca has a bit of a dilemma when it comes to who starts as the No.9 on Saturday. George was the man that replaced Guiu at half-time of the 5-1 win over Ajax and the Cobham graduate was also very impressive - scoring with one of his first touches of the ball in west London.

Joao Pedro will return to the squad for the visit of Sunderland after missing the win over Ajax due to suspension. The Brazilian can be used as the No.9 but Maresca has admitted in the past that he prefers the 24-year-old in a deeper role where he can get on the ball more and influence Chelsea's attacking play.

Maresca said on Friday: "Marc is a typical No.9, you will see physically strong, he is a box player, again he is [born in] 06, he can improve and he can do many things better and we are working with him every day to help him and as I said many times, he is going to play games with us.

"Then in terms of Joao [Pedro], we know that he can play as a No.9 or he can play as a No.10, in both positions I think Joao is very good but probably when he has another No.9 next to him, he is playing better."