The Blues suffered a 1-0 loss to Crystal Palace at Selhurst Park on Saturday, with Spaniard Fernando Torres missing a great late chance in south-east London.
Chelsea’s striker have managed a staggering two goals on their travels this season, and Neville reckons Mourinho’s lack of a proven finisher may have cost him the title.
“Probably [third favourites for the title] after the last two results,” Neville said on Sky Sports’s Monday Night Football.
“Other managers in the league – David Moyes and Arsene Wenger – have been criticised for their recruitment and getting it wrong in the summer.
“Jose Mourinho put all his eggs in one basket with Wayne Rooney. He made the bid for him and he thought he was going to get him and had the deal done.
“He thought he was in control but he was left with nothing and Lukaku goes on loan and he could have potentially helped Mourinho.
“So you have to say in some ways, they’ve been aware of the problem all season and they’ve been switching between Torres, Ba and Eto’o.”
Neville added: “Mourinho doesn’t throw leagues away from a winning position and at this moment in time, it is costing him.”
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