Marcus Rashford had the visitors ahead at the interval, but Foden levelled ten minutes after the break with a thunderous strike into the top corner.
After 80 minutes, Foden haunted United again, ghosting through on the left side of the box before slotting into the bottom corner.
Erling Haaland struck a late third to secure the three points at a jubilant Etihad Stadium.
Walker, who captained Pep Guardiola‘s men, praised Foden and explained his compatriot’s dressing room nickname, ‘The Sniper’ and when it was introduced.
“Since like 2017! He loves a shot. He practices and he puts the work in, he always does extra shooting. His goals are coming and he’s reaping the rewards. He needs to keep this up.
“When he comes in on his left foot, we call him ‘The Sniper’ because he likes to shoot! When he comes in on the left foot, he has the quality, calmness and composure to pick his spot. He took his first goal fantastically well.
“The second one, coming in off the left side, you don’t really see Phil much in that position, but for him to find that corner as he did, shows his flexibility. He can play on both sides and is even trusted down the middle at times this season.
“It’s a big part of the responsibility that he’s taken on for the team and we lean on him and we need important players like him. They win you games.
“This season he’s been nothing short of first class. That’s the standard that he sets for himself, that’s the standard that we and the manager set for him and that’s the standard he needs to keep up now.”
The Blues came from behind to win for the fifth time in the league this season and it was the first time that we had ever come from behind to beat Manchester United in a Premier League match, in the 29th occasion of us falling behind in this fixture in the competition (D3 L25). 
The victory also secures a league double over rivals United and Walker believes the half-time messages in the dressing room were crucial.
“I don’t think we played badly. I said in the dressing room at half time that it was not a bad performance. Sometimes you take your hats off to goals like that.
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“Marcus has hit a goal that has gone off the crossbar and into the net. Do I like conceding goals? No I don’t. Sometimes things happen in football.
“Now it was about the reaction from the lads. Us as leaders need to pick people up and not get too down. We know many games, especially here, it’s not over until it’s over and we’ll keep going until the end.
“Luckily, Foden came up with the equaliser relatively early on and then it’s just a matter of time until the second one comes if you keep the pressure on.”
