After a disappointing first defeat at Goodison Park yesterday, Jose Mourinho bemoaned a lack of ‘killer instinct’ and while the not so happy one was right, his use of substitutions were just at fault for his sides shortcomings.

With a starting line-up full of quality, the only real talking point was the debut for new signing Samuel Eto’o. With Romelu Lukaku being paraded to the home fans, there really is a worry that Chelsea will struggle in front of goal.

To be fair to Eto’o, he didn’t have a bad overall game, with the quality behind him, there will always be chances, and with more match sharpness, we will hopefully see the sort of striker that caused Chelsea a whole host of problems when he played for Barcelona.

Chelsea started the game well, having much of the possession, creating chances and perhaps with that ‘killer instinct’ would have been out of sight by half time.

As it was, some poor decision making from Chelsea’s experienced players lead to Steven Naismith giving Everton a 1-0 half time lead.

With a half time rollicking still ringing in the ears, Mourinho’s boys came out all guns blazing at the start of the second half, with more slack finishing from Andre Schurrle preventing a Chelsea equaliser.

Then came a Mourinho trademark, a bold, brass, substitution, off came Juan Mata and Schurrle, on came Oscar and Frank Lampard.

While you can’t fault Mourinho for trying to win a game, the double substitution wasn’t necessary, and in turn, helped Everton overcome the initial spell of pressure and grow into the game.

Like I have already mentioned, Mourinho got his tactics right, just the finishing let us down, and given the match fitness of Samuel Eto’o, perhaps all that was required was to replace him with Fernando Torres, who scored a wonderful goal in the last Chelsea game.

The double substitution changed the shape and feel of the team and they struggled to play with the same rhythm they had done before the change.

It turn, it was this that led Mourinho to make another bold substitution, replacing Ashley Cole with Fernando Torres.

Chelsea ended up in a 3-2-3-2 formation, devoid of any width, or general way of play, and it was Everton who had the better goal scoring opportunities and looked more likely to get a second.

Sending on a second striker and switching formations as dramatically as that is something you would expect in the closing moments of a game, but with half an hour left, the game was pretty much over for Chelsea by this point.

And it all stemmed from the first double switch, Mourinho could, and probably should, have remained a lot calmer, but the poor finishing was agitating him so much, it made him make rash decisions.

If your team is creating lots of chances but failing to really hit the target, you turn to your £50 million striker and see if he can do the job, you don’t need to change the whole shape and dynamic of the team.

And while Mourinho was happy to point out it was the mistakes of his experienced players at fault for the Everton goal, it was his changes which denied his team the chance to get something from the game.

This isn’t the first time Mourinho has made substitutions of this nature, in 2006 he hauled of Joe Cole and Shaun Wright-Phillips after 26 minutes against Fulham, a game they went on to lose 1-0.

Substitutions like this are brave to make, but only necessary if your team isn’t performing and Mourinho got it wrong yesterday.

Even this season, his substitutions against Bayern Munich in the Super Cup distorted the side, and allowed Munich to camp in the Chelsea half and led to their last minute equaliser.

Both times this season, Mourinho had his tactics right, but made the wrong substitutions at the wrong times, which have hindered his team’s chances of winning.

While many will point to the poor finishing and defensive mistakes for the reasons that Chelsea slumped to their first defeat of the season, Mourinho also has to take responsibility for his sides’ poor showing.

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