The Red Devils were knocked out of both domestic cup competitions earlier in the season but remain on course to achieve their primary objective of securing qualification for next term’s Champions League.
United are currently fourth in the Premier League table and need just one more win to guarantee their place in Europe’s elite club competition next season.
And Van Gaal feels that his side have coped well following the loss of a number of key players last summer.
Van Gaal told a news conference on Friday: “Of course [it is mission accomplished], because we have set the goals, the board and I, for what was reasonable.
“I think it was a big challenge. When I came here, there were a lot of players here and, nobody knows, but we have let go of 15 players and bought only five players.
“We also did it with different players to the year before because, when you lose players like Evra, Ferdinand and Vidic, that’s experience – defensive organisation.
“Then you renew your total defence because we have played more with Antonio Valencia, for example, as a right-back, and he was a right-winger. And then [Phil] Jones, [Jonny] Evans, [Chris] Smalling and [Marcos] Rojo have to play for us, and [Luke] Shaw, who is 19 years old.
“So, I think we did very good, but it is not good enough because, at the end, we want to be champions. Now, at the end, we want to be third because that is still possible. We can put pressure on Arsenal and that is what we want to do on Sunday.”
Van Gaal’s United side host Arsenal at Old Trafford in the Premier League on Sunday afternoon as they look to clinch a top-four finish.
A win against the Gunners would take United above Arsenal in the table, but the north London side have a game in hand over Van Gaal’s men.
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