Former Arsenal hero Charlie Nicholas has questioned whether Diego Costa will adapt to life in England easily.
Diego Costa was Atletico Madrid's top scorer last season, firing them to the La Liga title.
Jose Mourinho has attempted to solve this by moving Eto'o and Ba on, and signing Costa from Atletico, but former Arsenal footballer Charlie Nicholas has warned it may not be such a quick fix.
He told SkySports: "The signing of Cesc Fabregas is the big one; he’ll create a lot of chances for them. Diego Costa will be energetic and handle the physical challenge, although it will take him a bit of time to find his feet and I’m not convinced he’ll score bags full of goals in his first season."
The suggestion that Costa may not hit the ground running is a reasonable one, for the adaptation time new players need to new leagues frequently delaying their impact.
It even took Luis Suarez, a player Costa has been compared to, a year and a half, to hit the prolific form he hit with unstoppable consistency last season.
The issue Nicholas ignores, is the talent Costa has behind him, in Hazard, Schurrle, Oscar, Fabregas and Willian. With that cast of support, even an average return from him should see him hit around 15 goals next season.
The definition of success may not depend on Costa individually, but Chelsea winning silverware. If they do, then the number of goals he scores may become irrelevant.
How many goals will Costa score for Chelsea, and what number will define success?