Newcastle boss Alan Pardew admits he is still searching for the key to getting the best out of mercurial Frenchman Hatem Ben Arfa.
The 26-year-old has been used as a 'false nine' in the Magpies last two Barclays Premier League games with limited success - indeed, Pardew abandoned the plan before half-time in Sunday's 2-1 derby defeat at Sunderland.
At his best, Ben Arfa is a match-winner and has proved so already this season with a stunning strike against Fulham, but he can also be ineffectual.
Pardew has consequently used him in a series of different roles in an attempt to fine his niche, and that process is ongoing.
The manager said: "The truth with Hatem is we need a consistency in his play, and that's what we are searching for in the team.
"The decision-making process of Hatem is sometimes crucial, taking players on or playing it quickly.
"It's that balance that we are trying to get in the team that's right for Hatem and right for us."
Pardew's desperation to make the most of Ben Arfa's rich talent is all the more pressing with Newcastle's season having taken a significant turn for the worse in the last week.
They headed for the Stadium of Light intent on avenging April's shock 3-0 home defeat to the Black Cats and knowing victory would cement a satisfactory start to the campaign.
But they will welcome high-flying Chelsea to St James' Park on Saturday having slipped into the bottom half of the table and since, out of the Capital One Cup following Wednesday night's extra-time defeat to Manchester City.
skipper Fabricio Coloccini is unlikely to make the clash against the Blues as he continues his recovery from injury.
The Argentina international is back in training after a groin problem but has no football under his belt, while fellow central defender Steven Taylor, who suffered a recurrence of a hamstring injury in training last week, is still some way from returning.
Left-back Paul Dummett, who partnered Mike Williamson in the 2-1 defeat at Sunderland, is also out with a hamstring strain, meaning Williamson and Mapou Yanga-Mbiwa are likely to pair up, as they did in midweek against City.
Chelsea manager Jose Mourinho admits dropping his midweek cup heroes for the trip north will leave a bad taste in his mouth.
The Blues illustrated the strength of their squad when Mourinho made 10 changes for Tuesday night's 2-0 Capital One Cup victory at Arsenal.
But the majority of that team, including goalscorers Cesar Azpilicueta and Juan Mata, know they could find themselves kicking their heels against the Magpies.
"I don't say it's a headache, I say a bad feeling," said the Stamford Bridge boss.
"It's not easy for me to leave some players at home or on the bench because I think everyone deserves to play.
"To have all those choices is a good problem and to have all the players playing well and committed to the group is fantastic.
"But for me the responsibility of saying 'you don't play' is very hard because I feel I am being unfair with the ones I'm not selecting, because they are doing all they can to play and they can't do any more.
"When they come in they give everything, when they have a chance to play they play well.
"I change the team and they play a magnificent match so it's a difficult feeling for me because I'm unfair on them."
Chelsea can go top of the table, for a few hours at least, with a victory.
But despite heading to Tyneside on the back of a six-game winning run Mourinho knows only too well how tough a task they face - he has yet to win in the league at St James' Park.
"We know we have one of our most difficult matches of the season but we will try," he added.
"Going top is not important. It's important to go in the right direction and we feel we are improving - the quality of our game is good, the results at the moment are fantastic.
"We won every match in every competition in October including Schalke away, Arsenal away, Manchester City at home. They were very difficult matches and we won every one.
"But being top or not to be top at the moment is a question of one or two points, it's not important, although it's better to be first than fifth."
Mourinho has a fully-fit squad available for Saturday's trip apart from long-term absentee Marco van Ginkel.