Ji So-Yun opened the scoring after just seven minutes before Fran Kirby added a brace in the second half to secure a remarkable league and FA Women’s Cup double for the girls.
The title win came exactly 23 days to the day since Chelsea Ladies played their first ever game.
Emma Hayes named an unchanged starting side from the one that comfortably beat Liverpool 4-0 a week previously.
Hedvig Lindahl, with three clean sheets in her last four games, started in goal protected by a back four of Hannah Blundell, Niamh Fahey, Gilly Flaherty and Claire Rafferty.
Ji led the line up front supported by Kirby, Eniola Aluko and Gemma Davison, while captain Katie Chapman partnered Drew Spence in midfield.
The Blues started the game with the destiny of the FA WSL 1 title in their own hands and they used that authority in the title race to their advantage early on as they made a strong start.
Flaherty brought a routine stop from Hilde-Gunn Olsen in the Sunderland goal following Spence’s free-kick from the left, and Chapman almost got on the end of a lovely forward pass from Ji but was let down by a heavy first touch.
The hosts were soon ahead in the game as Ji netted her 10th goal of the campaign after seven minutes. Aluko used her explosive pace to escape down the left flank and delivered a perfect low centre for the supporting South Korean, who cushioned a composed side-footed finish inside the far post.
Ji’s measured side-footed finish nestles in the back of the net to give Chelsea Ladies an early lead.
Sunderland responded as Rachel Furness fired wide from a decent central position, however the league leaders continue to attack with pace and confidence as the half wore on. Ji combined intricately with Kirby and aimed for the far top corner with a curling effort that flew narrowly over, before Davison fired similarly off-target having cut infield from the right.
Hayes’s side continued to control proceedings and fashion opportunities as they searched for a two-goal buffer. Kirby missed the target by inches with a clipped finish over the onrushing Olsen after Ji’s pass had ricocheted fortunately into her path, before Tori Williams’s powerful pass back had her goalkeeper scrambling to make sure it didn’t roll in for an own goal.
In the final action of note in the first half, Aluko moved into space and whistled a drive inches wide from 25 yards out as the Blues went in to the break a goal ahead and in control.
The game restarted in a slightly more open fashion than Hayes might have liked, with Sunderland going close to a leveller within a couple of minutes as Bethany Mead escaped in behind. The striker, who netted a hat-trick against Chelsea in the fixture earlier in the season, opened her body expertly but could not place her shot on target.
Down the other end, Flaherty’s header from a left-sided corner rebounded back off the far post, while Aluko’s ferocious effort from the edge of the box was palmed away by Olsen. Lindahl gathered Emma Kelly’s header before Chelsea netted twice in six minutes to storm into the title race driving seat.
The quick-fire double came courtesy of Kirby, though the prodigious forward had Davison to thank for her first as the tricky winger advanced down the right again and supplied a teasing cross which Kirby converted sliding in at the back post.
Moments later, it was 3-0 as Kirby roamed in from the right flank and unleashed a swerving strike that flew past Olsen and into the far corner. It was her seventh goal in eight games since signing from Reading in the summer.
Hayes’s side had been solid at the back in recent weeks and demonstrated that defensive solidity again in the second half, with Lindahl dealing comfortably with a series of high balls into the box and those in front protecting her ably. At the other end of the field, Aluko seemed intent on adding her name to the scoresheet as she brought a good save from Olsen down low to the right.
Lindahl raced off her line to thwart Mead following a rare mistake by Fahey before the Swedish international was replaced for the final eight minutes by Marie Hourihan, the goalkeeper who broke her collarbone in a horrible injury on the final day of last season.
There was still time for late drama as we added a fourth goal to give the scoreline an empathic look, Davison exchanging a neat one-two with Kirby before slotting inside the far post. It capped a historic day for the Chelsea Ladies, who celebrated on the Wheatsheaf Park field in front of a record 2,710 crowd which included first team captain John Terry.
The Ladies will now begin their UEFA Women’s Champions League campaign this week against Glasgow City as they look to add to an increasingly-brimming trophy cabinet. Before then, however, they will enjoy the moment of sitting indisputably at the top of the English’s women’s game.