The former striker says Manuel Pellegrini's side missed the attacking powers of Sergio Aguero and David Silva.
Manuel Pellegrini’s side ran out as 2-1 winners against the Spaniards, with Kevin de Bruyne scoring a vital last minute winner to make it two wins from three in their group.
Toure had a big hand to play in both of City’s goals and once again showed why he should be played further forward rather than being burdened by defensive duties.
“Yaya was excellent on the ball for Manchester City, the rest of them struggled, it was a nervy night and the fans didn't get going at all,” he told Sky Sports.
"Where Manchester City find themselves in the Champions League at this time, Yaya Toure can hurt teams. When he plays as cover for the defence you lose so much of what can happen at the other end.”
One player who didn’t enjoy the best of evenings was striker Wilfried Bony as he failed to make a positive impression in the game.
The pressure is firmly on the Ivorian to step up and score the goals City need with star forward Sergio Aguero currently out injured.
Despite bagging two in the win over Bournemouth at the weekend, he was mostly a passenger against the La Liga side.
And Quinn says it just didn’t happen for him on the night, or indeed Manchester City who missed the attacking prowess of both Aguero and midfielder David Silva.
"It didn't happen at all for Bony. There was another incident when he turned his back on play after some good work from Sterling,” he added.
"The crowd got up, and you could hear some booing, and then he was taken off for a midfielder. It's difficult without Aguero, difficult without Silva, but thankfully Toure was there to offer some resemblance of a robust Manchester City attacking unit.