A double from Fran Kirby and goals from Sam Kerr and Pernille Harder helped to earn victory at St Andrew’s and secure our place in last four of last season’s competition.

After a goalless first half, substitute Kerr broke the deadlock on the hour mark when she headed home a cross from youngster Jorja Fox.

Kirby, who had also come off the bench, then scored two in two minutes with the first of her two goals a header from close range after Millie Bright’s initial effort hit the cross bar.

The No.14 was then picked out in the box by Jessie Fleming and Kirby took one touch out of her feet before firing a low effort to make it 3-0.

Another second-half substitute Harder then added a fourth in stoppage time when she headed in a Jonna Andersson cross.

Chelsea will now face a trip to Manchester City in the semi-finals but before then it’s back to league action this weekend as the Blues welcome Brighton & Hove Albion to Kingsmeadow on Saturday.

Emma Hayes made eight changes to the side that started our 6-1 demolition of Manchester United on Sunday.

Aniek Nouwen was handed her first start for the Blues in a back-three alongside Jess Carter and skipper for the night, Bright. Zecira Musovic was named in goal, making her third start for the club.

Drew Spence and Fleming both scored in the weekend’s 6-1 win at Manchester United and Hayes named them both in tonight’s starting XI. Spence lined up in central midfield alongside Sophie Ingle with Andersson and Fox occupying the wide positions.

Fleming was named in an attacking trio with Bethany England and Erin Cuthbert who returned to the side after missing the weekend’s victory at United due to an injury she picked up while away on international duty.

Hayes named a strong bench which included Kirby, Kerr and Harder.

Chelsea dictated play from the opening minute at St Andrew’s and Hayes’s side had the opportunity to take an early lead when the referee awarded the Blues a penalty just before the 20-minute mark.

After a darting run into the box, Cuthbert was fouled in the box, but the Blues were unable to capitalise with England diverting her spot-kick over the cross bar.

Spence struck fiercely on the edge of the box. It  was heading for the top corner but for a brilliant fingertip save from Birmingham goalkeeper Marie Hourihan.

Chelsea were enjoying the main share of possession, but the hosts were restricting us to very few clear-cut opportunities.

Nouwen had an effort from long-range but it didn’t trouble Hourihan in the Birmingham goal and the game remained goalless at the break.

Hayes brought Kerr into the action at the break, with the Australian replacing Ingle which meant Fleming dropped into a deeper role to partner Spence in central midfield.

The substitute nearly had an immediate impact as Andersson got in down the left and cut the ball back for the Blues forward, but she couldn’t generate enough power behind her strike to trouble the goalkeeper.

Moments later, Kerr did make a telling impact as she broke the deadlock on the hour mark. Fox delivered a perfect cross into the box and Kerr was there to head the Blues into a 1-0 lead.

Hayes made a triple change shortly after the opener with Charles, Harder and Kirby all coming into the action and within a matter of minutes Kirby had doubled the Blues lead.

Bright delivered a cross-cum-shot which hit the crossbar and fell into the path of Kirby who nodded in from close-range.

Two minutes later and Kirby had another after a great pass and move from the Blues. Andersson, Harder and Fleming were all involved with the latter picking out Kirby and the striker took one touch before firing in a third for Chelsea.

Harder then headed in an Andersson cross from the left to add a fourth and book our place in the semi-finals where we will face a trip to take on Manchester City.

For now, it’s back to Barclays FA Women’s Super League action and Chelsea will be aiming to make it three league victories on the bounce when we welcome Brighton & Hove Albion to Kingsmeadow on Saturday.

Following our clash with the Seagulls, the Blues begin our Champions League campaign at home with our first group stage fixture against Wolfsburg on Wednesday 6 October.

Birmingham City (4-3-3): Hourihan; Finn (Scott 80), Quinn, Lawley, Holloway; Whipp, Robertson, Pennock; Whelan, Sarri, Ryan-Doyle (Cowie 86)Unused subs Ramsey, Phillips

Chelsea (3-4-3): Musovic; Nouwen, Carter, Bright; Andersson, Ingle (Kerr 46), Fleming, Fox (Charles 65); Spence (Harder 65), England (Kirby 65), CuthbertUnused subs Telford, Leupolz, Reiten, ErikssonScorers Kerr 60 Kirby 70, 72 Harder 90+3

Referee Elizabeth Simms