Slaven Bilic urged his West Brom side to find their killer instincts, despite seeing them kick-off the season with a 2-1 win at Nottingham Forest.
The Baggies boss declared himself "pleased" to have claimed three points at what he regards as being a "Premier League" venue at the City Ground.
But he was less happy with what he felt was a lack of confidence in key moments from his side in the second half, after they had already amassed their 2-1 lead, thanks to goals from Kyle Edwards and Matt Phillips, which cancelled out an opening goal from Forest's Matty Cash.
West Brom were comfortable after the interval, but Bilic felt his side had been too relaxed – and should have been looking to kill the game off.
"In the second half, they did not create anything. They had corners and free kicks but we were defending very well in the box and outside it," said Bilic. "It was the first game, so nobody is fully fit.
"But what I was not happy with, with the quality we have and the team we have, was something else.
"You do not always have to score goals. But there were situations where we should have created chances and we did not.
"We had five clear opportunities to create a one-on-one; to go clear on goal. I don't mind if we had missed all five of those. But we did not create one.
"I felt that we were happy to be winning 2-1 and 2-1 can mean nothing. I want us to be confident, to have the composure and not to panic. That is the only part of the game – and it is a major part of the game – that I was not happy with.
"We should have created five good chances in the second half. We were one pass, one bit of confidence or one decision short in key moments.
"I am very pleased, of course. You only need to look around you at the crowd and the stadium – this is Premier League. It was like a Premier League game."
Both Baggies goals involved mistakes from Reds keeper Aro Muric, who had a tough Championship debut.
But Reds boss Sabri Lamouchi has faith that the Kosovo international will learn from the experience.
"We need to learn from our mistakes. Today we gave them two goals and that is not easy, to come back from that," said Lamouchi.
"Some defeats can bring positive things. We just need to work, but we know that. We need to learn from our mistakes and play with more personality and experience.
"When you start in the right way, as we did today, with the goal from Matty, you cannot allow the opponent to come back into the game in the manner that we did.
"The second goal can happen, many goalkeepers would have conceded that goal. The first one was of the type that can be avoided.
"But Aro is a young keeper and he has a lot of quality. He will help us a lot this season.
"He needs to learn from this. But he knows that. He needs to play with more courage and leadership, in his area; in the box."