The 21-year-old Belgium international has signed a five-year deal with Everton after completing a £28m move to Goodison Park from the Blues on Wednesday night.
The issue Chelsea have, is that, [following Lukaku’s departure], unless they can get anyone else in, they will be in the same situation they were in last year
And former Chelsea and Everton midfielder Stuart feels the west London side will be light on the striker front unless Mourinho adds another finisher to his squad.
“Diego Costa is a magnificent signing,” Stuart told talkSPORT. “There’s no doubt about his qualities and he seems to have settled in nicely. I don’t see him being any problems.
“The issue Chelsea have, is that, [following Lukaku’s departure], unless they can get anyone else in, they will be in the same situation they were in last year. Jose Mourinho doesn’t know who to turn to if anything happens to Costa.
“If he picks up an injury or suspension, where does he go? Will he look to Chelsea legend Didier Drogba? Let’s be honest about it. At his age, if he’s not playing at regular intervals, it’s not easy to step into a Premier League or Champions League game [and perform].”
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