The Manchester United manager should be careful about adjusting what has been a winning lineup.
This week, Robin van Persie announced that he is finally fit to return to duty for Manchester United, after missing the club's last five matches.
The striker tweeted the news that he is 'fit and able to play again', while stopping short of mentioning the upcoming Manchester derby this weekend.
Back to training with the group today. Was a great session. Happy to be fit and able to play again. Looking forward to my next game!— Robin van Persie (@Persie_Official) April 8, 2015
The 31-year-old striker will surely have an eye on the showpiece meeting at Old Trafford on Sunday though, even if Van Gaal was quoted by ESPN as saying the forward was unlikely to feature against Manchester City ahead of the win over Aston Villa.
But it would be wrong for the 63-year-old to adjust what has been a winning side in order to accommodate the returning Van Persie, or any other player for that matter.
The Netherlands' record goalscorer has not played since the 2-1 loss Swansea City, a game that is notable as being the last time United failed to take maximum points in a Premier League game.
Since the loss at the Liberty Stadium, Van Gaal has led United to five successive victories, a run of form that has anchored them in the Premier League top four and fuelled aspirations of a second place finish.
And against Manchester City, with United able to put some distance between the two clubs should they record a sixth successive league win, Van Gaal has to resist any intention to include a player he favoured during his time as Dutch boss.
With Wayne Rooney restored to what many consider his rightful position at the tip of United's attack, the Premier League giants look a much more coherent side, and more importantly, has allowed a series of midfielders to play in their own favoured positions. Marounane Fellaini, Juan Mata, Ander Herrera and Ashley Young have all impressed playing behind Rooney, with Van Gaal stripped of the pressure of fitting the United captain alongside former Arsenal favourite Van Persie.
It is why the former Netherlands boss should be brave when it comes to moving forward with his lineup, with it now clearer than ever that despite having Rooney, Van Persie and Radamel Falcao at his disposal, the club functions much better with the single striker playing.