Ralf Rangnick hailed Cristiano Ronaldo for scoring an "amazing" decisive goal as Manchester United returned to winning ways with a 2-0 victory over Brighton on Tuesday night.
But the interim manager lamented his side's failure to "kill the game off" as his pre-match calls for United to show no mercy fell on deaf ears.
Ronaldo, 37, opened the scoring with a fine strike shortly after half-time and the Red Devils took control of the match following Lewis Dunk's sending off moments later for a challenge on Anthony Elanga.
But it took until added time before United made the numbers advantage count with Bruno Fernandes scoring in the 97th minute.
The hosts went into the Premier League clash with the Seagulls on the back of two successive 1-1 draws during which they threw away the lead.
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Rangnick was desperate to address his side's habit of letting the opposition back into the match and told reporters on Monday: "We need to kill the game off. Score a second and third goal."
He used the same terminology after defeating Brighton, declaring he was not happy with his side's lack of a "lethal" edge against a team down to 10 men.
"It was a different game after the red card," Rangnick said. "[We] Should have killed the game off much earlier. We were not lethal in those moments to kill the game off."
Although he was not entirely pleased with United's performance, the German reserved special praise for Ronaldo after the striker ended his six-game goal drought.
"[It was] Very important not only that he scored but it was an outstanding goal," Rangnick added. "It was important for all of us, but his overall performance was one of the best since I arrived here."
Brighton boss Graham Potter echoed his opposite number's praise for Ronaldo, saying: "[We were] Punished by a world-class finish by a world-class player."
Elsewhere, David de Gea was lauded by his manager after continuing his fantastic season with an acrobatic save to deny Jakub Moder's header.
"In the last 10 to 12 games, that has happened a few times," Rangnick said of the Spanish shot-stopper producing a special moment. "[It was a] Brilliant save from Jakub Moder and that is why we have one one of the best goalkeepers in the world."
Victory over Brighton saw the Red Devils leapfrog West Ham into fourth place ahead of their trip to Leeds on Sunday.
However, Arsenal and Tottenham could overtake Rangnick's side in the race for Champions League qualification if they win their games in hand.
