"I've got no doubt on Valero's technical ability to pick the right pass at the right time," Mowbray said.
"There were spells in the first half when you could see the cleverness and the weight of his pass releases players to run away and get into goalscoring areas.
"I'm sure he'll be integral in a lot of pleasing plays for us as we move on."
The West Brom manager believes there is more to come from the Spaniard once he gets up to speed with the different fitness requirements of the higher-tempo English game.
"He has talked to me about the Spanish pre-season as opposed to the English pre-season being like night and day," said Mowbray.
"They get the balls out, have a bit of a tap about, put a few passes together and get themselves ready to go and play.
"He's done no physical running whatsoever really in his preparation, so I would suggest he's behind the requirements to play in the Premier League week in, week out.
"But we'll get there over the course of the next few weeks and months and his talent on the ball is unquestionable. I'm sure he'll be a good acquisition for us."




