Adam Lambert has namechecked some of his American Idol favourites this week, but he admitted that it is "kind of early" to choose a winner.

The 'For Your Entertainment' star became the first former contestant to return to the show as a mentor last night, as he guided the Top 9 through their Elvis Presley week performances.

According to the LA Times, he was asked to name his "standouts" of the night during a chat with reporters backstage. "Vocally, it would be Michael (Lynche), I think he's probably got my favourite voice. Crystal (Bowersox), then Siobhan (Magnus) and Katie (Stevens) are both really strong singers. It's kind of early to really pick the favorites," he said.

When asked what the differences are between this season's singers and his own year, he replied, "(This season is) definitely geared toward more of a singer-songwriter genre and sound. They're all great singers, they all have great voices, they're very likable. I think our season was a bit more diverse, musically."

Lambert will perform single 'Whataya Want From Me' on tonight's results show, which airs 9/8c on Fox.