Manuel Pellegrini believes Yaya Toure is being unfairly targeted by critics this season.
The Manchester City boss accepts the Ivory Coast midfielder may have fallen below his own high standards but is convinced he is still doing a crucial job for his team.
Toure, the driving force behind two title successes, has been criticised for a lack of significant output in recent weeks and pundits and fans have suggested he could be past his best.
The 32-year-old was lacklustre in Wednesday's Capital One Cup semi-final first leg defeat at Everton but Pellegrini insists this was a blip.
He said: "He's not so old. I think he's a player who is very important, an experienced player and he knows how to play every game.
"Maybe to play the whole season three games a week, he is not able to do it, but I think he can play in the way he's playing now. He can make a difference.
"Every time people say we have not got the squad we need, people always look at Yaya, but remember he scored three times in the last few games.
"Maybe against Everton he didn't play very well but every player has better or worse games. You can't talk always about it being because he's older. Everyone can have a bad game.
"Maybe it's the image, the body language, but if you review the numbers of Yaya, each game he runs as much as every team-mate."
Pellegrini's defence of his player comes after Toure expressed anger and frustration at missing out on the African Player of the Year award for 2015.
Toure, the winner for the past four years, was beaten into second place on this occasion by Borussia Dortmund's Gabon striker Pierre-Emerick Aubameyang.
Toure was complimentary about Aubameyang, who scored 41 goals for club and country in 2015, but felt his own contribution as the African Nations Cup-winning captain was not sufficiently recognised.
He told radio station RFI: "I am very, very disappointed. It's sad to see Africa react like this, not giving any importance to African (competitions). I think it brings shame on Africa. It is indecent. What can we do?
"We, Africans, we do not show that Africa is important in our eyes. We prioritise external achievements over our own continent. It is lamentable."
Pellegrini, meanwhile, has also spoken in praise of another of his players, David Silva.
The Spanish playmaker, another key performer in City's recent success story, turned 30 on Friday.
Pellegrini said: "He can be a top player for many more years now he is 30. He's not based on force, or speed, he's based on his style and his talent. You can get more talent and use it for your experience.
"David demonstrates in every game how important a player he is. He is a different player, so technical with so many key passes during the game.
"Not only for me, for Manchester City it is a gift to see him playing every week. The fans always appreciate what he does in the game so I hope he will continue the same."