Manchester United face added pressure to land Southampton defender Luke Shaw after Alex Buttner signalled his desire to leave the club.
United are in a tug-of-war with Chelsea, of whom Shaw was a boyhood fan, to sign one of England's most promising talents.
But the club's hand may have been forced after Dutch defender Buttner seemingly signalled his intention to leave Old Trafford after only two seasons at the club, leaving Patrice Evra United's only left back.
Buttner told Dutch paper De Telegraaf: "Van Gaal never gave me the chance in the Dutch national team, despite being voted man of the match 14 times at Manchester United.
"Apparently he is not very confident about me. So I think this is the right moment to leave."
The 25-year-old's agent later affirmed that his client, who arrived in 2012 from Vitesse Arnhem, is likely to leave Manchester, saying it was "not an option" to remain at United and hinting at a move to Russian club Dynamo Moscow.
"In the past two years, Louis van Gaal has ignored Buttner time after time so what kind of perspective does he have when Van Gaal becomes his new club coach?" he told Voetbal International.
"Patrice Evra signed a new contract and with Luke Shaw they want to buy another player for Buttner's position. To stay at Manchester United was not an option for Buttner. Dynamo Moscow has great plans for the future and they want to challenge for the title."
Van Gaal, who has earned plaudits for the way the Netherlands have started the World Cup, has lined up Dutch left-back Daley Blind as another possible option should a move for 18-year-old Shaw fail.