Manchester - David Moyes, the Manchester United manager, admitted it would have been impossible to replace talisman Wayne Rooney at Old Trafford.
Rooney celebrated signing a new five-and-a-half year contract by sealing United's 2-0 Premier League win at Crystal Palace with a superb volleyed finish to double the advantage following Robin van Persie's penalty.
Following the success at Selhurst Park which put United sixth in the table, Red Devils boss Moyes saluted the 28-year-old England striker and believes he will only get better after putting him in the bracket of the best players in world football.
Moyes said: "He's a really important player and you think about the amount of clubs who wanted to sign him. He would have been too difficult to replace. There aren't enough top players out there that you can get cheaply or easily.
"Wayne's one of them, one of the top players. He shows it week in, week out for us and you can see the change in him - his leadership, what he's trying to bring to the team.
"We want him to keep at it and I'm sure he will. He's a boy who wants to continue to get better."
Moyes, Rooney and United now travel to Greece for Tuesday's Champions League last-16 tie against Olympiakos.
And the United chief, who has endured a difficult first term in charge following Sir Alex Ferguson's retirement, hopes his men can gain in belief from their victory in south London and finish the season on a high.
Moyes added: "We have a really big European tie coming up on Tuesday night and our focus goes on to that.
We wanted to win the game to make sure we go into that game in good form and confidence. It's such a big game for us.
"We haven't played for 10 days so I wanted to make sure all the players were ready and focussed for the game and ready to perform again.
"We've a few injuries but hopefully we will get a few of them back for Tuesday. They have a chance. I have to see how Phil Jones and Jonny Evans are.
"Rafa (Rafael) as well. We'll have a look at them tomorrow and hopefully see if they can join us."
Palace, meanwile, remain two points above the relegation zone, but Eagles manager Tony Pulis insists his side need to start achieving positive results.
Pulis said: "Every game whether it's home or away matters. We have to start collecting the points. We're in it with 12 other teams. It will go right to the end.
"Whether it's against the top four or five, there's always three points. We have to scrap and fight for everything against every team.
"Today was disappointing. The penalty gave United the leg up they were looking for.
"We needed one or two of our forward players to play better than they did today in terms of possession.
"Even the second goal, Marouane seems to fall over the ball when there is no-one around him. The goal comes from that. You need your top players to play well.
"Marouane has been fantastic for us this year. He still gave us enormous commitment, but that was probably as poor as he has played in possession of the ball. He's very good at that."
Pulis was able to call on fit-again Glenn Murray after the striker ended a nine-month injury nightmare.
Pulis added: "I was pleased with Glenn. It was just disappointing we couldn't keep him on a bit longer. That was enough for him today. That will do him the world of good."