What are Chelsea trying to do by leaving the 31-year-old William behind and going after the 33-year-old Mertens?

Due to the economic losses caused by the league lockout, clubs have had to tighten their purse strings when formulating transfer budgets, and the players who will soon become free agents in the summer have naturally attracted the attention of many teams, with Napoli striker Mertens being one of them. So far, the Belgian has been rumored with Chelsea, Inter, Atletico Madrid, Milan, Juventus and other teams, from the recent media reports, Chelsea seems to have been on Mertens. But this also makes a lot of people feel puzzled: the Blues put more than six years of William does not renew the contract, but prefer to go to the introduction of William than two years older, and only in the Belgian, Dutch and Italian leagues played in the veteran, this Mertens in the end what is so good, let Chelsea so fascinated?

In my last article, I analyzed the reason why William's contract was difficult to renew from a tactical point of view, simply put, William's role in the team is not irreplaceable. At the beginning of the season, William solved the problem of the team's forward progress, helping the team to obtain a wave of consecutive wins, but after the international match day in November, the opponents have adjusted their strategies, amplifying the weakness of the Blues' attacking force, Chelsea's record has also seen ups and downs as a result.

And William didn't do much to help the team in the process, especially after the New Year, when he only scored 1 goal and 1 assist. And the excellent play of Giroud, Mount, Gilmour and Pedro before the season was halted gave the team more options in terms of moving forward. In this case, Chelsea no longer had to make an exception to give a three-year deal for the Brazilian.

Comparing Mertens and Willian's stats, it's easy to see the difference in their on-field roles. Mertens is not as good as Willian in terms of breaks, passes and other propulsive stats, but doubles the Brazilian's goal tally, and that's despite playing eight fewer games. And it's not just William who is not as effective in attack as Mertens in the Chelsea team, it's only Abraham who is currently scoring double the amount of goals. Mertens, who has scored double-digit goals in all seven of his seasons at Napoli, will be able to improve the team's attacking efficiency.

Particularly in the Champions League, Mertens' attacking power is what Chelsea lacks. This season, Mertens helped the team in Liverpool and Barcelona in front of the whole body back, gave people a very deep impression. Rich experience in the Champions League is what Chelsea desperately needs. The team has just trained a new army soon, and for the time being does not have the strength to compete with Liverpool and Manchester City for the Premier League crown. Seeking a breakthrough in the Champions League, and letting the young players accumulate experience and self-confidence is the main task of the Blues outside of the league's competition for the fourth place, which requires an experienced player to sit in the team, and Mertens obviously meets this condition.

Mertens is a late bloomer who has been in the starting lineup since he was 29 years old, which requires strict self-discipline and hard training to keep him in shape. If such a veteran is put into the team, it can set a good example for Chelsea's young players. Excellent attacking efficiency, rich experience in the Champions League, and good professionalism are all three points that meet Chelsea's current needs. So, to give up William and introduce the older Mertens, it is also a normal operation.

Of course, many people are worried about whether Mertens can keep up with the pace of the Premier League, the intensity of the confrontation and the rhythm of the game in Serie A, and the Premier League is not on a level, a 33-year-old and has never played in the Premier League of the old, even if you can maintain a higher attacking efficiency in the Serie A, come to the Premier League may not be able to. Indeed, adapting to the rhythm is almost every first-time player in the Premier League to face the problem, the body of the small Mertens if the Premier League field, there is also the risk of attacking efficiency discount.

But the Belgian's prospects are not necessarily pessimistic. The chart above shows Mertens' appearance statistics since joining Napoli, and as you can see, the fact that he has been able to secure a starting position is directly related to the change in his role on the field - since 2016, the Belgian has ceased to play the role of a winger and has moved to become the team's main center forward. It is important to know that the intensity and rhythm of the game in Serie A is not as good as in the Premier League, but the tactical use of the bottom is quite deep, and the extraction of space on the field is more adequate. A height of only 169 centimeters in the center, can be in front of the chain defense to show such a high attacking efficiency, enough to see its use of space on the pitch has a very high attainment.

To Napoli's away game against Cagliari, for example, in the first half, Napoli did not find too good a chance to face the opponent's dense defense, and the second half, Gattuso adjusted the frequency of the attack in the middle of the road, the number of times that Mertens took the ball from the first half of the 18 times to 27 times, the number of times that the number of shots on goal also grew to 4, the team's quality of the attack has been significantly improved. It was also the Belgian's catch-and-shoot after getting away from his opponent in the box that helped his team take three points from the away game.

Mertens' ability to use space is what Chelsea lacks. As noted above, the Blues' up-and-down campaign after November's International Day was the result of a lack of attacking ability. Abraham, although not bad, has a high demand for space, and once entangled by the opponent, the entire team's offense may be dumbed down. It was not until Giroud returned to the starting lineup, giving the team a reliable fulcrum up front, that the problem was solved.

However, given Giroud's age, it's still unclear whether he can play a sustained pivot role, and there's still room to increase the depth of the forward line. Mertens in the last 10 games, five games as a substitute, 113 minutes of playing time, he contributed to the team's 1 goal, 3 assists, 10 shots and 5 key passes, "microwave oven" characteristics are very obvious. If the Belgian can join, then Lampard's adjustment program will be more abundant.

Mertens can enhance the depth of the team, can make the team's attacking routines more abundant, his understanding of the pitch space and the use of Abraham's growth can also provide a great help, this kind of player is worth the pursuit of Chelsea. But if you can really come to the team this summer, there are still some difficulties that need to be overcome by Mertens and Lampard*** together in order to stand firm in the Premier League.

There is no more obvious problem than Mertens' age. Despite his good work ethic, at 34 years old, he is definitely a senior player in the Premier League. Although the Premier League wide-open style, can let Mertens get more space, but want to be based on the Premier League, certainly to enough running based on, especially Chelsea's pass-and-control play, need to be supported by a high press, which for the Belgian's physical fitness, is certainly a small challenge.

Moreover, it is difficult to avoid the ups and downs that come with old age, and this season, Mertens has had more obvious "symptoms". At the beginning of the season, Mertens was the absolute mainstay of Napoli, including the European preseason, including 8 games, a **** scored 6 goals, the state is quite good. However, after entering October, Mertens' form declined, playing 13 times on all fronts, with only a goal and an assist against Red Bull Salzburg, and the Belgian also lost his starting position. Although this has something to do with the team's managerial change, the key to the problem still lies in the maintenance of their own form. If he wants to integrate into Lampa's tactical system as soon as possible, Mertens will have to adapt to the new rhythm while also trying to maintain his athletic performance.

Also, although Mertens can enrich the team's tactical play, it does not mean that Lampard's pressure will be reduced. Mertens in Belgium and the Netherlands when playing, has been serving as a winger role, landing in Serie A after the performance of the general, until after the change to play center forward to break through the hall of fame, so it can be predicted that he can only serve as a center forward in Chelsea a position. In other words, once Mertens joined, then Chelsea will have three pure center forward.

This means that it will be difficult for all three to be on the same roster for the same game. After all, there are only seven substitutes, and with a center forward on the bench, it will be difficult for Lampard to bring two pure centers to the bench. From this point of view, Mertens may be difficult to get stable playing time in the early stage of joining, for his integration is very unfavorable. Therefore, after Mertens joined, Lampard needs to consider more comprehensively, reasonable deployment, in order to play as soon as possible the function of the Belgian.

According to reports in the Italian and British media, Mertens has made it clear that he prefers to go to Chelsea, and the negotiations between the two sides are currently stuck on the issue of treatment. If a compromise can be reached with each side giving a step forward, then the possibility of Mertens appearing at Stamford Bridge next season is high. The Belgian can bring help to the team, the Premier League is a new challenge for the veteran, and I hope that in this summer, Mertens will be able to stand on the stage of the Premier League as desired to show their style.