Manchester United hope to have Wout Weghorst signed in time for Saturday's derby against Manchester City.
United are racing to register Weghorst in time for the derby after agreeing a deal to sign the Holland striker for the rest of the season.
Weghorst's loan move must be completed by noon on Friday for him to be eligible to make his United debut at home to Manchester City in the lunchtime kick-off.
The 30-year-old flew by private jet from Istanbul to Manchester on Thursday to complete his medical, and United sources say that while there is a possibility of him playing Saturday, it is not certain, reports the Daily Mail.
Weghorst was cleared to leave Besiktas – where he has spent the first half of the season on loan from Burnley – after United agreed to pay the Turkish club £2.5million in compensation to rip up the existing agreement.
The former Wolfsburg and AZ Alkmaar striker hit nine goals in 18 games for Besiktas, and also scored twice for Holland against Argentina in the World Cup quarter-final last month.