Alvaro Morata and Romelu Lukaku will be under pressure to fire their teams back into the Premier League title race when the misfiring strikers clash in Chelsea's showdown with Manchester United on Sunday.
Chelsea forward Morata and United front man Lukaku were the toast of their clubs after celebrating their close-season transfers with a barrage of goals.
But, with Chelsea and United battling to keep pace with leaders Manchester City, Morata and Lukaku have lost their midas touch at the wrong moment, putting them under the microscope at Stamford Bridge this weekend.
United manager Jose Mourinho splashed out £75 million (Dh360m) to sign Lukaku from Everton after persuading the Belgium international to snub interest from Blues manager Antonio Conte.
Lukaku was off to a fast start, netting 11 times in his first 10 games.
However, the 24-year-old player finds himself in the midst of a barren spell stretching back six games to the end of September.
United fans have grown frustrated by Lukaku's lack of contributions outside the penalty area, prompting Mourinho to chastise Old Trafford crowd for failing to give the striker enough support in last weekend's win over Tottenham.
Lukaku responded to the doubters by conceding he is still a work in progress.
"You can't judge me as the finished article. I'd rather have a career where year after year I improve rather than going to the top and decline," he said.
"I know I have a lot of talent, but I want to have more assists, I want to make sure when my team is in difficulties they can count on me."
After missing out on Lukaku, Conte settled for Morata as an expensive consolation prize.
Morata hit the ground running with seven goals in his first seven games following his club record £58m move from Real Madrid.
But, like Lukaku, the 25-year-old Spaniard has failed to score in his last six games, earning criticism for some lethargic displays.
Morata also had to claim he had been misquoted after an interview in which he appeared to hint he would not stay with Chelsea for long because he does not enjoy London's hectic lifestyle.
In the circumstances, Morata and Lukaku could do with silencing the critics by producing a priceless winner at the Bridge.
Both players carried hefty price tags because of the belief they were ready to deliver when the stakes are highest.
That will be the case in west London this weekend as champions Chelsea try to claw their way back into the title race.
Fourth-placed Chelsea are four points behind second placed United and nine points adrift of table-toppers City.
Conte's side crashed to a 3-0 defeat at Roma in the Champions League on Tuesday, erasing the momentum from successive league wins over Watford and Bournemouth.
United are five points behind City after winning only one of their last three league games, although they made it three successive wins in all competitions by beating Benfica in midweek.
Mourinho will be hoping for better luck on his latest return to Chelsea - the club where he won three English titles and was sacked twice - after United lost both their visits last season.
Abused by Chelsea fans during United's 4-0 and 1-0 defeats, Mourinho insists he does not attach special significance to the fixture.
"It isn't a big thing. It's normal, it's football. One day you are in one club, the next day you're in another club," he said.
Conte, who will give N'Golo Kante a late fitness test on his hamstring injury, concedes Chelsea no longer have any margin for error if they are to overhaul United and City.
"Now there is a big problem for all the teams that want to fight for the title and this big problem is Manchester City," Conte said.
"If they continue in this way it will be very difficult to fight for the title."