Rafa Benitez says he was "pleased" with Joselu's performance against his former club Stoke City.
Newcastle United won 2-1 yesterday to move up to fourth place in the Premier League.
Jamaal Lascelles and Christian Atsu were on target for Benitez's side at St James's Park.
Atsu gave Newcastle an early lead, but Xherdan Shaqiri levelled for Stoke after Joselu failed to convert three good chances either side of the break.
Lascelles headed United's winner for the second week in a row.
Asked about Joselu's performance, manager Benitez said: “For a striker, when you have chances, it's important to score.
"For a striker playing against Stoke, maybe even more. I'm really pleased with his contributions. He was winning in the air, he was holding the ball.
“A lot of positives for a lot of players and still plenty of room for improvement.
"I don't say that we have to play perfect games every time, but we know we can improve little things and that will give us more chance to win games.”
Joselu, 27, joined Newcastle in a £5million deal last month.
Benitez added: “I wouldn't say I was worried about missing the chances.
"I'm really pleased we can create chances. After you have to score. In this kind of game, if you concede, you will say we had the chances and we'll be talking about that.
"Sometimes you will score goals you don't deserve, and sometimes you will conced goals you do not deserve to. We deserved to win.”