Alan Pardew believes keeping Wilfried Zaha at Crystal Palace after Tottenham launched a late bid to sign him could prove crucial to their season.
Chairman Steve Parish rebuffed Spurs' £12 million bid as the summer transfer window drew to a close, and was rewarded on Saturday when the midfielder set up the opening goal and then scored the winner as the Eagles beat promoted Middlesbrough 2-1 at the Riverside Stadium.
Asked how important that decision was, manager Pardew replied: "Of course, that was very important. The chairman made that very, very clear, that he wasn't going to sell him, and I think he meant it, as he proved, so it was important.
"He didn't start the last game because of the transfer situation, but he was terrific today, not just the goal and the assist, which I have been really working with him on, but his defensive qualities today against George Friend, who bombs up and down that line, were exceptional."
It was Zaha's 16th-minute cross which provided £27.5m new boy Christian Benteke with the chance to open his Palace account with a towering header, although the man he beat in the air to score, Daniel Ayala, made amends seven minutes before the break in equally imperious style from Stewart Downing's corner.
But the winner was all the midfielder's own work, if with a little help from Friend, whose woefully short back-pass allowed him to fire home from close range.
Pardew will hope Benteke's contribution is the first of many as he attempts to establish himself once again at Selhurst Park.
He said: "It's very important for a striker to get that first goal, and as soon as the cross came in, you kind of knew. I don't think any defender could defend him in that position when he's coming on the back of you like that.
"He's a bit like Andy Carroll. If the ball is in the right area, it's almost impossible to defend."
Boro head coach Aitor Karanka admitted his side had not been at their best for long periods in the game, but was left to rue two late penalty decisions which did not go his side's way as first Scott Dann and then Damien Delaney survived handball claims.
Karanka said: "I don't need to say anything. You said it was handball and I think everybody could see both of them so for that reason, I don't need to say anything, just to say that today we have lost from mistakes.
"We have lost and we have to learn because today has been a good example that if we don't play with our intensity, we are in the Premier League and we are going to pay for mistakes.
"If we arrived today unbeaten, it's because we played the first three games with an amazing intensity and today, especially in the first half, we didn't play with that intensity.
"In the second half, we had chances, we had a lot of things, but again it's a good game to learn that we can't drop our intensity for one second in the Premier League."
Asked if his players would learn from a sobering experience, Karanka added: "I hope so, I hope so because for sure I have learnt.
"They are intelligent and for sure they have learnt that we have to play in the way we played the first three games and in the way that we played the second half today."