Mikaela Shiffrin says she is dealing with post-traumatic stress disorder following a crash in November and will not defend her gold medal in giant slalom at the Alpine skiing world championships.

Mikaela Shiffrin said she will still race the slalom and team combined at worlds but said she's "not there yet" with giant slalom.

Returning before next month's world championships and chasing a record-extending 100th World Cup win, the American struggled with her timing on both runs.

The American holder of a record 99 World Cup wins suffered a deep puncture wound when she fell in a giant slalom race on Nov. 30 in Killington.

American champion Mikaela Shiffrin won't defend her giant slalom title at the world championships as she grapples with the mental impact of a major injury.

American Mikaela Shiffrin will not take part in the giant slalom event at the world championships in Austria, saying on Monday that she is not yet mentally ready after her recent return from injury but will now compete in the team combined competition.