Manchester United manager Louis van Gaal believes the upcoming transfer window will be a busy one, and lauded David de Gea as the club's best player this season.
De Gea's future has been the subject of intense speculation in recent weeks, with Van Gaal appearing to confirm Real Madrid's interest in the goalkeeper following Sunday's 1-1 draw with Arsenal.
At United's end-of-season awards ceremony on Tuesday, the Dutchman said he expected to be active once the transfer window reopens, and was full of praise for De Gea's performances.
"Our selection is out of balance - we have managed to be fourth but we have to manage to be champions," Van Gaal commented.
"We also have to improve our selection. It shall be a rough summer for a lot of players but I think a top club like Manchester United has to do that.
"I can promise I will do my utmost best, that we shall fight until the end and that we make the right decisions when you purchase players.
"Also when players are leaving it's a natural process that the fans are not forgetting them.
"Which player has impressed me the most? I think David de Gea because in the beginning of the season I observed him and I analysed him and then I see his progress in the season.
"I have to say it's fantastic development and as a manager you have that perspective - that's why I think David de Gea has impressed me the most."
