The 63-year-old watched Thursday’s frantic 3-2 win against Arsenal from the directors’ box at Old Trafford, where he was on the sidelines for the first time on Sunday as Patrick Vieira’s men came to the north west.
Rangnick had precious little time to work with the players given the swift turnaround, but United played on the front foot from the outset with impressive intensity and energy.
Their performance petered off after that breathless opening 30 minutes but Fred stepped up late on to secure an important 1-0 victory with a superb curling effort from the edge of the box.
“Overall I am more than happy,” United boss Rangnick said. “I was positively surprised by the physical state and intensity.
“The first half hour was amazing. I felt it was extremely high tempo, high intensity, always on the front.
“The only thing that was missing in this first half hour was scoring one or two, if not three, goals.
“But it was clear that you cannot play the whole game, 90 minutes, on this kind of intensity level.
“But, still, even after that we had control of the game. Second half, we started the game well and, in the end, we deserve to win.
“I am more than happy with the clean sheet. Beautiful goal with this weak right foot from Fred and, as I said, for me, it was about gaining control and we had control most of the time of the game.
“Maybe the last three or four minutes, of course, they took all the risk they could, we had to defend a few corner kicks and free-kicks but we did that in a very brave way.
“Harry (Maguire) being injured, coming back again. It was a perfect first game for us to play.”
Rangnick may be celebrating with a glass of red wine and a nice meal, but his focus quickly turns to Wednesday’s Champions League match against Young Boys and the Premier League trip to Norwich.
The coming days provide the chance to build momentum and underline his philosophy to the players, who have taken onboard instructions in a way that has impressed the interim manager.
“I must admit I was surprised,” Rangnick said of the group’s immediate response.
“I was a bit surprised because not only did we play Thursday, a late kick-off, we had two days less to recover compared to Crystal Palace and we had not even a full training session yesterday because it was 45 minutes, it was pouring (with rain).
“It was not just Manchester weather, it was just disgusting – it was heavy, raining, windy, so it was almost impossible to train in a concentrated and focused manner.
“But they still did it, those 45 minutes were important on the pitch.
“We explained to them how we want to play, which manner we want to play and the rest was video footage, a lot of personal conversations with players, individually and in groups, explaining to them how we want to play.
“As I said, I didn’t expect them to play on that kind of level after such a short time.”
There was some more positive news for Rangnick post-match as injured midfielder Paul Pogba shared an update on his recovery from a hamstring problem, insisting on Twitter he is “on the road to coming back stronger”.
Crystal Palace manager Patrick Vieira felt his side were not brave enough in possession and could have caused more problems for United in Rangnick’s first game.
“It is frustrating of course because we make it really difficult for them to create chances,” the former France midfielder said.
“I think we defended well as a team and we had that moment to score the first goal (when Jordan Ayew put wide in the 75th minute) and we didn’t take it.
“And on the other side, they had that opportunity and they take it. They take it quite well from Fred.
“It is disappointing and, again, losing that way it’s frustrating.”