Doctor Who newcomer Jenna-Louise Coleman has been praised by co-star Matt Smith for breathing new life into the show.

Speaking at the Doctor Who Experience in Cardiff, the actor described his new screen companion as “smoking”, and added, “Jenna is doing wonderfully well.

“I look back to my first day and I was like a rabbit in the headlights,” Matt revealed. “She is much more assured.”

He also revealed that having Jenna-Louise on the show had created a different dynamic to his previous sidekicks Amy and Rory – who departed two weeks ago in the episode The Angels Take Manhattan.

Rory used to take care of Amy quite a lot so the Doctor became a weird old grandfather,” Matt explained. “He was ostracised in some way. So it is nice having a different dynamic. I think the Doctor has done well on both accounts — I think they are both hot. Jenna is a joy and I lucked out again.”

However he added that the Doctor was “very sad” to see Amy go, saying that she “came to define an era” of the show.

“They were great friends and companions,” he admitted. “But now we move on and the character moves on. It is about Jenna-Louise Coleman.”

The actress made her surprise debut earlier this series in the opening episode, Asylum Of The Daleks.