How did The Doctor ended up outside and Clara lost inside when TARDIS was zapped by the scavengers?

In the Doctor Who episode Journey to the Center of the TARDIS, The Doctor turned off the shield of TARDIS and suddenly scavengers zapped it and pulled it inside. When they dumped the TARDIS, the gate of TARDIS was still closed, but The Doctor was outside. How? As I recalled, opening the doors required efforts, too (meaning doors weren't soft shut).