Lopez struggled initially last season and finished the campaign back on loan at his former club, but has quickly found his feet this term, opening his account in old gold in the League Cup earlier this month.
He showed his quality when he left Preston defender Liam Lindsay for dust before carrying the ball all the way into the opposition’s box and finishing powerfully past Daniel Iversen.
Minutes later, another returning Wolves player, Raul Jimenez, almost grabbed the second goal in his second spell at the club, but the Mexican’s flick from close range went the wrong side of the post.
At the other end, Marshall Munetsi headed Callum Lang’s effort off the line after a spell of pressure from the hosts, who had started slowly.
Rodrigo Gomes almost doubled Wolves’ lead on the stroke of half-time, but Iversen was at full stretch to get a hand to his low strike from the edge of the box.
Both sides made changes after the break with the game at a crossroads, but it was the visitors who prevailed, with Armstrong emerging from the bench to double his side’s lead on 71 minutes after a nice one-two with Jimenez set him free inside the area.
Lopez then finished off another slick move to double his tally from the edge of the box with eight minutes remaining before Thompson produced a smart finish of his own to make it 3-1.