After a slow start to the contest, which was in keeping with the two tight matches between the sides last season, Chelsea began to take control midway through the first half and we deservedly went in front through a smart finish by Kerr, who expertly turned in a low cross by the sharp Fran Kirby.

There could have been further goals in the remainder of a half we dominated, as we looked to get a second that would almost certainly have killed off the home side’s hopes, but just as against Man City in last Saturday’s Community Shield, our finishing wasn’t as sharp as it should have been.

Leah Galton almost made us pay on the stroke of the interval with a header that came back off the crossbar, but she was eventually rewarded just 10 minutes before the end of the contest, as she tapped in at the back post to draw United level.

We had clear chances either side of that goal, most notably a pair of one-on-one opportunities for Erin Cuthbert, but Red Devils goalkeeper Mary Earps was in excellent form and ultimately we had to settle for a point from a game we should have won.

With our main title rivals Manchester City and Arsenal both victorious this weekend, it leaves the Blues playing catch-up early on, but as Emma Hayes was keen to stress after the game, there is still plenty of football to be played over the next nine months.

For the first game of our WSL title defence, Hayes made only one change as a midweek injury for Ann-Katrin Berger meant she was replaced in goal by Carly Telford. The experienced back four of Maren Mjelde, Millie Bright, Magdalena Eriksson and Jonna Anderson – who were all praised by Hayes ahead of the game for their work ethic in training – lined up in front of Telford and there was no shortage of industry or quality in the midfield trio of Melanie Leupolz, appearing in the WSL for the first time, Sophie Ingle and Ji So-Yun.

In attack, Kirby started her first league game since taking on Man United last November, alongside Kerr and Guro Reiten. That meant new signing Pernille Harder had to settle for a place on the bench, a week on from appearing for Wolfsburg in the Champions League final.

As with both of our previous meetings with the Red Devils, who are starting only their second season in the English top flight, it was a case of the Blues dominating possession and looking to break down a stubborn defence that was more than happy to drop deep to limit the space in behind.

Although Jane Ross had the first shot in anger, looping a speculative effort just the wrong side of the post with only five minutes on the clock, we slowly began to assert ourselves in the attacking third and Reiten threatened an opener with a low strike that forced Earps into the first save of the game.

It soon became apparent that our best opportunities were going to come down the flanks – and that proved to be the source of our opening goal, thanks to an excellent combination between Kirby and Kerr. The former used her pace to get on the end of a through-ball by Mjelde and she slid a low cross into the perfect area, allowing the Australian to put last weekend’s Community Shield misses behind her with a clinical finish from close range.

Kerr thought she had another just three minutes later, as she got on the end of a pass from Reiten and confidently slid the ball past Earps, but this time the smile was wiped off her face by a raised flag from the assistant referee. Replays showed she had started her run half a second too early, but her confidence was clear for all to see in our next attack, as she shifted the ball past a defender and fired her shot just a foot or so wide of the far post. What a difference a goal makes.

While Kirby’s most eye-catching moment of the first half was undoubtedly the pass to set up Kerr’s opener, her manager would have had a different view of things. With 10 minutes left in the half, our No.14 showed the other side of her game when sprinting back down the right touchline to help out her defence with a timely interception in her own penalty box, highlighting the attitude and application Hayes expects of every player, regardless of their position.

With the interval just around the corner, the Blues could have been two goals to the good as Ji produced a sublime pass to loft an inch-perfect pass to Kerr, who took it in her stride and struck a sweet effort that went straight into the midriff of Earps. Had it been either side of the keeper, the end result would almost certainly have been the ball nestling in the back of the net.

Instead, we were almost pegged back with the last touch of the half, as Leah Galton’s speculative header came back off the crossbar seconds before referee Rebecca Welch blew her whistle. As unjust as an equaliser would have been, it was a timely reminder that all our hard work could have been undone by one lapse in concentration.

Kerr was in the thick of things early in the second half, once again showing off her excellent movement to get on the end of an inviting cross by the marauding Mjelde. This time, however, Abbie McManus did just about enough to put our No.20 off and her finish flashed over the bar.

United boss Casey Stoney, an ex-Blues skipper and briefly our player-manager, wasted no time changing things up in the second half as she brought on Jackie Groenen, another former Chelsea player, in a bid to take control in midfield. The change almost had an immediate positive effect, as Telford was called upon to make a fine save to deny Katie Zelem.

Hayes responded in kind, adding the industrious Cuthbert to the mix in place of Ji just before the hour mark, and there was another Chelsea connection about the home side’s second substitution, as men’s team right-back Reece James’s sister Lauren came on. Bethany England followed her onto the pitch a few minutes later to replace goalscorer Kerr.

The Red Devils were finally showing a bit more intent in the attacking third, but that simply served to open up more space for the Blues, and in particular the lively Cuthbert, to try and exploit. It took two wonderful saves from Earps to deny her a second goal off the bench in as many weeks, the first from a Kirby pass and the second a half-volley from England’s cross to the back stick.

Those missed opportunities came back to bite us with only 11 minutes left on the clock, as Groenen broke clear down the right and fizzed a low pass across goal that Galton tapped in to draw the home side level.

With another goal now needed to start our WSL campaign with a win, Hayes turned to her new signing Harder, sending the Dane on along with Jess Carter as Reiten and Andersson made way. Harder led a rapid counter-attack soon after her arrival, which ended with Leupolz blazing a half-volley over the bar.

Harder started another break deep into stoppage time, which was excellently worked by Kirby onto first England and then Cuthbert, whose curling effort from the far side of the penalty box was blocked by a last-ditch challenge that sent the ball squirming out for a corner. There was still time for Kirby to slice a volley up into the air, but that proved to be the final kick of what turned out to be a frustrating opening game of our title defence.

The Blues will look to get our maiden WSL win of the season on the board next Sunday when we host Bristol City in our first game at Kingsmeadow since February. Kick off is at 12.30pm and you can watch it via the BBC Red Button.

Manchester United (4-3-3) Earps; Smith, McManus, M Turner, Batlle (Okvist 74); Toone, Ladd, Zelem (c); Hanson (Groenen 53), Ross (James 60), GaltonUnused subs Ramsey, A TurnerScorer Galton 79Booked Zelem 85

Chelsea (4-3-3) Telford; Mjelde, Bright, Eriksson (c), Andersson (Carter 80); Leupolz, Ingle, Ji (Cuthbert 58); Kirby, Kerr (England 66), Reiten (Harder 80)Unused subs Orman, Blundell, J Fleming, Spence, CharlesScorer Kerr 25

Referee Rebecca Welch

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