Scotland’s Steph Twell’s involvement at the World Athletics Championships is over after she failed to progress through the 1500m heats in Berlin.

Twell, who turned 20 yesterday, produced a notably below-par performance as she crossed the line in 4:18.23 minutes – good enough for 12th place.

And the former world junior champion confessed she was at a loss as to what went wrong in the Oltympiastadion.

"I'm not sure what happened - I was working really hard to stay on the inside and I think I lost a lot of energy just trying to stay near the front," said Twell.

"There was a lot of argy bargy. They just had another gear and I think I just used all my energy trying to get into a good position.

“I felt good coming here and I can't believe it but I’ll have to go back and discuss it with my family and coach and move on.”