Pep Guardiola, who had suffered his worst five-game start to a season after taking just eight points, saw his team's domestic frustrations alleviated by Sheffield-born Walker's 28th-minute strike at Bramall Lane.

City, buoyed by a 3-0 UEFA Champions League win in Marseille, was on top from the outset and only a fine display from Blade goalkeeper Aaron Ramsdale limited the damage.

The result leaves Chris Wilder's side still winless, while providing a confidence boost for a City outfit whose next top-flight clash is at home to champion Liverpool.

Ferran Torres's glancing header from Joao Cancelo's cross forced a fine early stop from Ramsdale, who also saw Aymeric Laporte steer a close-range effort just past his near post.

Rodri's ferocious 25-yard strike was too hot to handle as the goalkeeper parried it over the crossbar in slick conditions amid heavy rainfall in Sheffield.

The Blades continued to rely on their last line of defence when Ramsdale thwarted Torres after the Spaniard slid in to connect with Raheem Sterling's cross.

Walker, a product of the Bramall Lane academy, forced the breakthrough with a low, skidding shot that nestled in the keeper's bottom-right corner.

The Blades, who have never beaten City in the Premier League, remained firmly on the back foot in the second half, living dangerously as Kevin De Bruyne's attempt flashed narrowly wide.

Ramsdale was to the fore again soon after, tipping Riyad Mahrez's free-kick wide, while substitute John Lundstram fired over at the other end in a rare opening for the home side.