The German international made an instant impact with a 20-minute debut cameo at Norwich City last week where, playing just off the front, he helped knit our play together as we came from 1-0 down to secure a point at Carrow Road.
Lewis had longer to show his worth when he came on for injured Jermain Defoe after 39 minutes at West Brom on Sunday.
Once again he was everywhere, buzzing around in the forward areas and forcing a fine save from Ben Foster before being involved in the move that led to Gareth Bale crashing home the winner.
"Lewis has made an immediate impact in the team in both games," said Andre.
"He offers further options playing from the channels coming in. We haven’t seen him in this position yet, but he finds comfort there because played it before for Mainz.
"At the moment he’s playing fantastically well. Hopefully we will continue to see him progress."