Unlike during his first spell at Chelsea, Jose Mourinho is uncertain of his best line-up - and that has led to inconsistent results this season.
After defeats to Everton and Newcastle this year, Chelsea were extremely fortunate to get away with a draw at home to West Brom before the international break.
Referees' chief Mike Riley has since apologised to Steve Clarke's side for Andre Marriner awarding that last-gasp penalty and rightly so. For Mourinho to say it was a penalty, well, I'm not sure what game he was watching because they got away with one there.
Although that result came about in a large part due to a very good performance from West Brom, there are more questions than answers at Chelsea at the moment.
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Does Mourinho go with John Terry, David Luiz or Gary Cahill at centre-back? Willian, Juan Mata, Eden Hazard and Oscar all want to play in the hole so who gets the nod? Should Fernando Torres, Samuel Eto'o or Demba Ba lead the line?
Mourinho is still trying to decide on the best way of playing with the players at his disposal and, inevitably, that has led to hit-and-miss performances on the pitch.
Fortunately for him and Chelsea, most of the other sides in the title race - Arsenal aside - have struggled, too. Mourinho would be under a bit more pressure if Manchester United and Manchester City hadn't been as inconsistent.
You could certainly point to the men in charge as a factor - while inconsistent Chelsea, United and City have new men at the helm, top of the table Arsenal still have long-term boss Arsene Wenger in charge.
I'm not sure there's any excuse for Manuel Pellegrini, though - with the players he has in that squad there has to be a question mark over the manager and attitude of a team which plays so well at home and so badly on the road.
For Chelsea and Mourinho, however, it's about settling on a preferred line-up.
Of course, with all the games teams have to play these days - not to mention the strength in depth Chelsea have - there has to be an element of rotation.
But I'd like Mourinho to say to his side after a disappointing performance 'that wasn't good enough', keep the same team and send them out there again in the next game to prove they can do it.
Chopping and changing the side hasn't helped the players build understanding and familiarity on the pitch, which is so important.
The one player Mourinho has come out and publicly backed has been Oscar and as a result he's been their best player this season.
That's an example of one of Mourinho's best attributes: extracting the best out of players who believe in him.
But he's also ruffled a few feathers so far in his second stint, with Mata, in particular, losing out.
Mourinho likes functional, hard-working players. He sees more beauty in the way Andre Schurrle plays than Mata. That's not wrong or right - he's won many titles with those values.
But I just hope with Mata he's not trying to prove a point. If he wins the title and doesn't play Mata again this season we'll all say 'fair enough' but the truth is I've watched a lot of Chelsea this year and you can't tell me they are a better side without Mata than they are with him.
Sometimes managers get blind spots with players and, having seen the contribution Mata has made over the last couple of years, I find his treatment quite hard to understand.
After the result with West Brom, Mourinho will have been disappointed to have lost his players for the international break because the first thing you want to do is get them in, go through the game and bounce back as soon as possible.
But they have a good chance of getting back to winning ways at West Ham this weekend.
The injury to Winston Reid is a big blow for the hosts and with Andy Carroll still out, two of their powerhouses will be missing.
Sam Allardyce will have to find a solution at the back to replace Reid - but he may also need to consider a different approach to the one they've employed in recent weeks.
Playing without a recognised striker and flooding the midfield has produced some good results - most notably the 3-0 win at Tottenham - but after the defeat at Norwich last time out it may be time to go back to a more direct style of football.
And, with Carroll out, there could be an opportunity for Carlton Cole to step up to the plate on Saturday.
The big front man scored against his old team when these sides met at Upton Park last season and he'll have fond memories of his impressive performance in that game, which helped the hosts to a 3-1 win.
He'll also want to prove his doubters, who think he isn't good enough to be back at West Ham, wrong.
The fans at Upton Park may turn on him quicker than they do with the other players, but this is a great chance for him to show what he can do, be the focal point of West Ham's attack and, as long as he's fit, I expect Allardyce to unleash him.
However, I've got to go for a Chelsea win here, and I reckon they'll take it 3-1 to bounce back from that West Brom result.
Sam Allardyce will be hoping to get a fast start and catch out a few of the Chelsea players who have been away on international duty, but I think Chelsea will have too much.
A defeat could edge West Ham, who have been unfortunate to lose Carroll, the man they built their plans around, to injury, closer to the relegation zone but I expect them to move up the division eventually.
With Carroll coming back in the New Year and Carlton Cole gaining fitness, a return to a direct approach - which has been successful for Allardyce before - could see them get their season going again.