Madrid - Barcelona fielded their fabulous four against Leganes on Saturday for the first time this season but it was only after Antoine Griezmann went off that his replacement scored the winner.
Lionel Messi, Luis Suarez, Ousmane Dembele and Griezmann all started but Giezmann departed in the 57th minute before Arturo Vidal poked home in the 79th, fortuitously placed as Messi's cross cannoned into his path.
When Barca signed Griezmann last summer for €120 million from Atletico Madrid, many wondered where the Frenchman would fit into their stacked front line, which would have swelled further had Paris Saint-Germain come to terms over a deal for Neymar.
Gerard Pique has said key players were even prepared to alter their contracts to facilitate Neymar's arrival and while Messi has dismissed talk of a rift with Griezmann, doubts persist.
"For me, he's a player that has just arrived - and at a club like Barca, who play a little differently from other clubs," said Clement Lenglet last month.
"He helps us a lot with his talent, with his defensive effort, because he is a player who sacrifices a lot for the team. I don't think there is any problem with Antoine Griezmann."
Many expected Griezmann to reinforce and eventually replace Suarez down the middle but Ernesto Valverde has been curiously reluctant to field him in the position closest to the one he thrived in for Atletico last season.
With Messi indispensable on the right, Griezmann has been used most often on the left, taking the place of Dembele when he has struggled for fitness or form, which in the case of the mercurial 22-year-old has tended to be often.
But Griezmann has not looked comfortable, despite the occasional glimpses of excellence such as the two goals he scored against Real Betis in August, which looked set to give lift-off to his Barcelona career. Instead, too many matches that have passed him by.
"I am learning a different philosophy of playing and a different position," said Griezmann last month. "You have to learn, improve, adjust your movements. In two months, you cannot have it 100%.
"It will come and I know my teammates want the best out of me. I want that too, I demand the best of myself every day and I think I'm on the right track."
Griezmann is not alone. Barcelona sit top of La Liga, ahead of Real Madrid on goal difference but dreary performances have not looked worthy of league champions and still less, winners of the Champions League.
They face Borussia Dortmund at Camp Nou on Wednesday, on the back of a goalless draw at home to Slavia Prague earlier this month that means qualification from Group E is far from guaranteed.
Anything other than a win is likely to leave them needing at least a point against Inter Milan at the San Siro in a fortnight's time.
Valverde would appear unlikely to throw Messi, Suarez, Griezmann and Dembele together again for Dortmund, who will offer a sterner test than bottom-club Leganes.
But his eagerness to roll the dice last weekend with four forwards, and Messi in a deeper role, suggests he recognises the lack of creativity and has begun to reach for more daring solutions.
In defence, Valverde might have to be imaginative too. Jordi Alba is out with a hamstring strain while Nelson Semedo and Clement Lenglet are both struggling with calf problems.
Gerard Pique is also missing as he serves a one-match ban, meaning there could be a place for Samuel Umtiti, who has made only three appearances this season.