Mary Earps will line up for Manchester United against Arsenal on Friday night but it could have been the other way round. 

The Gunners made an attempt to buy the 30-year-old before the start of the new Women's Super League season. 

Marc Skinner's side turned down the offer despite the goalkeeper's contract being set to expire next summer. 

Ahead of tonight's WSL clash, we examine the transfer saga and Earps' future. 

United gamble

Earps was the star of England's World Cup campaign, saving a penalty in the 1-0 defeat to Spain in the final and winning the Golden Glove award. 

Her form persuaded Arsenal to make a bid worth over £100,000 — a world-record fee for a goalkeeper in the women's game. 

United turned the offer down. Their desire to keep the best stopper around is natural but they have taken a gamble in not accepting the fee. 

Earps' contract would have expired this summer if not for the Red Devils triggering a one-year extension. 

Now United must persuade her to sign a longer deal and fast. Should they fail, they will be faced with the option of selling in January or losing a valuable asset for nothing at the end of the season. 

This is exactly what happened in the case of their striker Alessia Russo, who now plays for Arsenal. 

United turned down a world-record transfer fee of £500,000 in January this year, only for the England forward to join the Gunners on a free at the end of the season. 

Contrary to beliefs

There were reports that Earps was eager to leave United this summer but the 30-year-old has rejected those claims. 

Speaking after playing in England's recent 2-1 victory over Scotland, the goalkeeper spoke about the scrutiny she has been under. 

Earps said: "It's been tough to be honest, it's been a tough few weeks for me personally. 

"I have tried to keep my head down and get on with things, but it's been hard to see how I've been portrayed at times. 

"Having your body language and your facial expressions heavily scrutinised. 

"I care deeply about Manchester United as a club and all I have ever tried to do is give my absolute best, from the moment that I joined and give my all to the team. 

"I've only tried to push the team to reach its full potential and demand more, because I truly believe the club is capable of greatness." 

Title bid

It may take a display of greatness to keep Earps at United. 

Should they not be in contention for the WSL title by January, there will be a temptation to cash in on their goalkeeper. 

At that stage, foreign clubs will be able to negotiate a pre-contract agreement, while Arsenal are likely to resurrect their interest. 

United certainly seem to be preparing for life without their stalwart having signed American keeper Phallon Tullis-Joyce from OL Reign in September for a record fee in excess of £100,000. 

The Red Devils just missed out on the WSL title last season and it may take another challenge to retain Earps. 

A victory against Arsenal would be a strong sign that it is a journey that United are ready to take.