Van Gaal had overseen United's longest sequences of matches without victory since 1990.
Manchester United manager Louis van Gaal paid tribute to Wayne Rooney after his winner against Swansea City lifted him to second place in the club's all-time list of goal-scorers.
Rooney superbly flicked in Anthony Martial's cross with 13 minutes to go at Old Trafford on Saturday to give his side a 2-1 victory that ended their nine-game winless run and left them fifth in the Premier League.
The United captain's third league goal of the season took him past Denis Law to 238 goals -- behind only Bobby Charlton's club record of of 249 -- and Van Gaal hopes a first home victory since 7 November will trigger an improved run for both Rooney and his side.
Van Gaal, who had overseen United's longest sequences of matches without victory since 1990, said: "It is amazing and that at the age of 30 years.
"You have to say that of course now we are playing much more matches, but still it is an achievement. For me, it is more important he scores now and he scores today (Saturday).
"He scores also a fantastic goal, with his left foot behind his right foot, and you cannot imagine what a goal that is. A great goal.
"All the players have done their utmost best and that is very important for the manager. I hope it is a fantastic starting point for the team and for him."
United, whose 0-0 draw against Chelsea last Monday meant that they had failed to score in five of their previous eight home games, produced an improved performance.
As well as creating the winning goal, Martial headed in the game's opening goal two minutes into the second half and Ashley Young, who set him up, also stood out.
Van Gaal described his starting formation, with a three-man defence and Young and Martial as wing-backs, as "risky".
He was in danger of seeing more points dropped when Swansea, who had won their previous three games against United, equalised through a Gylfi Sigurdsson header with 20 minutes to play.
'Lower the pressure'
But Rooney's goal was a reward for a more adventurous approach by the United manager.
"Amazing is that you can perform the game plan like we have done in the first half and the second half in a risky style under this pressure. That is positive, I think," Van Gaal said.
"Also against Chelsea we played very risky because we want to press. The players want to press. It is a risk to play that.
"Still we are the dominating team, against Chelsea and today against Swansea. That is why I am proud they can do it under this pressure.
"They have showed it this season many times, but now the situation is different. Now I have a good hope this is a starting point for more.
"You cannot predict (what effect a win will have). Only it shall raise the confidence and lower the pressure because the players had a lot of pressure to do it in 90 minutes against an opponent that is not so easy.
"The opponent is also playing in a way that makes it difficult to score, with 10 players behind the middle line. That is why I am happy we scored the two beautiful goals."
Swansea, who remain just one place above the relegation zone, did not include England midfielder Jonjo Shelvey in their squad, but caretaker manager Alan Curtis said that the 23-year-old was still part of his plans.
"We had a good talk about it before we came away. He trained this morning with a group of players," Curtis said.
"Jonjo has a terrific ability. We all know that. We need him and hopefully he will play a part to the end of the season for us."