Thorstvedt reckons Harry Redknapp will be making a huge mistake if he is tempted into a swap deal.
"Drogba is past his peak," said the Norwegian, speaking to talkSPORT. "He's a fantastic player, one of the best strikers in the world, but he's on the way down.
"If you want to invest for the future and build up a team you should look at a younger guy. Drogba is a machine, he can terrorise defenders, but it also takes a while to see when the downturn has started. Although he had malaria problems last season, he wasn't quite there like he was before."