A Delaware judge who ordered NASCAR driver Kurt Busch to stay away from his ex-girlfriend says there's a "substantial likelihood" of Busch committing acts of domestic violence in the future.

In a 25-page opinion Friday explaining why he issued the no-contact order this week, the judge said it was more likely than not that Busch "manually strangled" Patricia Driscoll in his motorhome at Dover International Speedway in September and smashed her head into a wall.

Busch has denied the alleged assault, which is the subject of a separate criminal investigation, but the judge said Driscoll's version of events was more credible than Busch's.

At the same time, however, the judge said he believed that Driscoll presented false testimony at times during the hearing on her request for the no-contact order.