Wayne Rooney is the man on most of our minds, so far as transfer goes. After all, Jose Mourinho has declared the Manchester United forward Chelsea's primary target this summer. We've already seen that Rooney's acquisition wouldn't have any impact on the team's compliance with Premier League squad rules (and noted that UEFA compliance is far less important), but now there's some worry over whether or not acquiring him would mean too many strikers and not enough playing time for all of them. Let's explore that idea.
If Rooney comes, does someone have to be sold? Leaving aside Mourinho's declaration that nobody's going anywhere, there are two salable striker assets on the squad: Demba Ba and Romelu Lukaku. There's no reason to sell the latter, so if we brought in Rooney and ditched another centre forward we'd go into the season with Rooney, Lukaku and Fernando Torres as the strike force. Is three centre forwards better than four?
There are two costs associated with having an extra player on one's team. The first is financial -- if Chelsea can sell Demba Ba they get a transfer fee and some nominal wage relief. For the Blues, this isn't a major concern, mostly because Ba isn't very expensive (and they're not going to be able to sell Torres unless another club takes crazy pills). The second is a cost associated with playing time. Footballers need to play to develop and stay content, and more players fighting it out for one position means less playing time for all.
Here's why that's a non-starter so far as Chelsea are concerned: The two players who'd suffer the most in a four-striker regime are Fernando Torres and Demba Ba. Neither of them need development time -- they are what they are, and neither is (or should be) in the club's long-term plans. There's no reason to assume that Mourinho would end up using Lukaku as anything other than a second choice/rotational player, so his time is safe. And frankly, if Torres is unsettled by not getting any time, that makes him more likely to take a paycut to go somewhere else, which is beneficial, not detrimental.
What are the benefits to having four players rather than three? We can get an idea of how importance depth is by recalling what happened twelve months ago, when Chelsea went into the season with two strikers. One promptly got hurt and we ended up riding Fernando Torres even further into the ground. The more strikers we have, the less likely that we're going to have to rely on one out-of-form player through thick and thin.
And there's another benefit to having more strikers on the squad -- it allows for tactical flexibility. While the 4-4-2 hasn't been in vogue at Stamford Bridge for years, being able to play it is better than not. That's harder to do with fewer centre forwards.
Indeed, the last two Premier League champions have fielded four centre forwards. Manchester City had Sergio Aguero, Carlos Tevez, Edin Dzeko and Mario Balotelli. Manhester United used Robin van Persie, Wayne Rooney, Javier Hernandez and Danny Welbeck.
What's the motivation for having fewer players again?