The winger launched an unstoppable left-footed strike into the net from distance and then completed a second half brace with a vicious low drive at Prenton Park.
Filippa Angeldahl’s first goal of the season had opened the scoring just after the half-hour mark when she latched onto an incisive aerial ball from goalkeeper Sandy MacIver.
But the hosts turned the game on its head either side of half-time through former City duo Gemma Bonner and Natasha Flint.
City responded well to the setback though with Jess Park tapping home for the second successive Conti Cup fixture moments after Liverpool went into the lead.
Kelly then took centre stage to seal the points, despite a stoppage time effort from Mia Enderby.
What Happened
Just as we had against Arsenal on Sunday, City started brightly at Prenton Park and had the first real sight of goal inside seven minutes.
It fell to Lauren Hemp, who pounced on a loose pass across the Liverpool box, but her effort from point-blank range was well saved by the onrushing Laws.
That early scare shook the hosts into life, with their aggression and energy putting pressure on City during our spells of possession.
Indeed, our backline had to be alert on a couple of occasions to prevent Matt Beard’s side from translating that into genuine sights of goal, with former City forward Flint going closest with a snapshot inside the area.
But City weathered the storm and would find the breakthrough just after the half-hour mark through Angeldahl.
The Swede raced onto MacIver’s long ball over the Liverpool defence before coolly slotting home past Rachael Laws.
For all of City’s intricate passing play, it was a direct ball from the goalkeeper which sparked the opener, and the players raced to congratulate MacIver and Angeldahl in equal measure.
The goal added some extra bite to a chilly night at Prenton Park, with both sides pressing to gain a foothold on proceedings.
And the hosts would draw themselves level in the 45th minute when former City defender Bonner hooked Grace Fisk’s header from a corner into the net beyond MacIver.
It had been a dramatic end to the half, and it was equally frenetic after the restart, with Liverpool taking the lead inside two minutes.
A mix-up at the back for City saw Flint pick up possession inside the area, before our former striker dinked the ball over the onrushing MacIver.
Undeterred, Gareth Taylor’s side mounted a defiant response and drew level soon after, when Park reacted quickest to tap home on the rebound from substitute Kelly’s vicious low drive.
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A captivating clash continued to deliver, with MacIver producing an exquisite save to tip the lively Flint’s long-range effort over the bar as the hour mark approached.
At the other end, it looked like Deyna Castellanos had handed City the lead with a typically remarkable effort but, after taking two Liverpool defenders out of the game with a clever feint onto her left foot, sent a rasping drive just wide of the far post.
But a spectacular third would follow with 20 to play.
After working the ball from left to right, Kelly picked up possession and cut in on her weaker left foot.
And when the ball bounced up invitingly for her under pressure from a Liverpool defender, the winger sent a rasping volley into the top corner, triggering audible gasps from both sets of fans at Prenton Park.
Kelly was clearly in the mood and would double her account for the night with ten to play.
Picking up the ball from Castellanos, the England international knocked the ball onto her right foot and fired a decisive low drive into the far corner in front of the travelling City supporters.
Gareth Taylor’s side were in the driving seat, and were the width of a post from making it five when Castellanos was sent clean through soon after.
A clinical finish from Enderby late on provided the hosts with a glimmer of hope, but City held on to maintain our 100% start to our Conti Cup campaign in the process.
Player of the Match: Chloe Kelly
Another remarkable individual display from a player who just seems to be getting better and better.
Two incredible strikes from the substitute provided the quality that City needed to pick up the points.
How we lined up
Gareth Taylor made nine changes from the side who were edged out by Arsenal on Sunday.
Sandy MacIver started between the sticks, shielded by a back four of Kerstin Casparij, Steph Houghton, Esme Morgan and Julie Blakstad.
Ruby Mace sat at the base of a midfield three, with Filippa Angeldahl and Laura Coombs given licence to get forward and join the attack.
At the sharp end, Jess Park and Lauren Hemp started on the flanks with Deyna Castellanos leading the line.
LIVERPOOL XI: Laws, Matthews (Nagano 46’), Parry, Fisk (Hobinger 46’), Daniels, van de Sanden (Hinds 46’), Taylor, Bonner, Holland (C) (Clark 46’), Enderby, Flint (Kiernan 76’).
SUBS: Spencer, Roman Haug.
CITY XI: MacIver, Casparij, Houghton (C), Morgan, Blakstad (Aleixandri 88’), Mace (Hasegawa 46’), Angeldahl, Coombs (Roord 68’), Park (Fowler 68’), Castellanos, Hemp (Kelly 46’).
SUBS: Keating, Stokes, Ouahabi, Shaw.
What it means
With Leicester not playing in this match week, City now sit top of Group B with two wins from two, three points clear of the Foxes in second place.
Liverpool meanwhile are still searching for their first win of the Conti Cup campaign.
Up Next
City are back in WSL action on Sunday 12 November when we face Brighton at the Joie Stadium.
Kick-off is set for 13:00 (UK), with the match available to watch live on CITY+.
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