Top scorer Kirsty Linnett pounced minutes after the interval before Kerys Harrop extended the lead two minutes from the end of normal time.
The victory keeps David Parker’s side in pole position in the league with three wins and two draws to their name.
Despite lying in midtable, Manchester City Women entered the second half in form having won their last four fixtures in all competitions.
However, apart from a nervy spell prior to Harrop’s late goal, Blues never looked likely to let all three points slip from this one.
After a scrappy start, the first clear cut chance of the match fell to Blues in the 21st minute. Kerys Harrop brought skipper Karen Carney’s corner from the right under control and saw her blocked effort fall kindly to Hannah Keryakoplis on the left only for a low drive to be deflected wide.
Carney’s follow up corner also carved out a decent half-chance for Blues as the cleared set piece fell to Chelsea Weston 20 yards out but her thunderous volley fizzed just over.
The best chance of the first-half came in the 34th minute. Linnett’s pinpoint cross from the right met the head of Keryakoplis yards out but the former Liverpool forward couldn’t keep her effort down.
While the hosts dominated the first half, Manchester City did have a goal chalked off four minutes before the interval. Ex-Blues midfielder Izzy Christiansen’s corner from the left swung in but the referee had spotted a clear foul on goalkeeper Rebecca Spencer in the build up.
Blues couldn’t have asked for a better start to the second-half as Linnett bagged her fourth goal of this FA WSL campaign. The ex-Arsenal striker charged down a clearance before racing through to coolly slot a low effort beyond Karen Bardsley.
Then came an unexpected halt in play that would result in 12 additional minutes being added to the end of this game. Referee Sian Piret appeared to injure her right wrist during a fall and was eventually replaced by fourth official Mark Billingham after receiving treatment.
The lengthy break hampered the ebb and flow of the game but Manchester City almost sparked to life only for England international Jill Scott to scuff a good effort wide of the post from the right in the 71st minute.
Two chances fell in the 74th minute; Carney’s right-sided cross picked out a downward header from Remi Allen at the far post that was blocked by Bardsley before Weston sent a low drive just wide of the left post.
The visitors from the north were coming on strong and rattled the woodwork twice within the space of four minutes. Spencer’s punched clearance fell only as far as Besty Hassett who struck the bar before Natasha Flint saw a deflected shot wriggle through only to hit the left post.
Fears of a comeback from the away side were extinguished in the 88th minute when Harrop rose to meet a cross from the right with her head and reel away in celebration, but only after an agonising wait to see her effort deflect off Bardsley, trickle across the line and go in off the right post.
The extended period of time came and went with no further goalmouth action allowing Blues to extend their lead at the top to four points.
Blues Ladies starting XI: Spencer, Weston, Sargeant, Mannion, Harrop, Keryakoplis (Westwood 90), Allen, Linnett, Carney (C), Potter, Moore.
Subs: Baggaley, Simpkins, Wellings, George, Torkildsen, Haines.
Manchester City Women starting XI: Bardsley, Holbrook, Houghton (C), Johnston, Scott, Christiansen (Young 90), Hassett, Nightingale, Lipman, Flint, McManus.
Subs: Brougham, Turner, Brooks, Harding.