The Senegal striker was so prolific when he first joined the Magpies but his goals had dried up before he headed home powerfully just after the half-hour mark at St James' Park.
"All strikers when they are not scoring don't feel like they have done their job. Goalscorers want to score goals and he is always disappointed if he hasn't scored," said Pardew.
"He has had a few good chances in these last few games, but that was an important goal tonight - how important, we will have to wait and see.
"He had a couple of big chances before that and snatched at them, and it just goes to show where he was, really.
"Goals can settle a player down and hopefully it will because he has not been as powerful and as good as he had been."