The director has struggled to find employment in Hollywood after filming the flop I Know Who Killed Me - and now he admits his star's personal problems turned a one-month shoot into a four-month headache.
He tells the Los Angeles Times, "Most days we wouldn't know what happened (with her). We just found out that day.
"At some point it became, 'How can I complete the movie?' That was my one and only goal - not to have it fall apart."
Sivertson admits Lohan wasn't even present when he filmed her two characters' climactic scenes in the thriller - and he had to resort to desperate measures to finish the movie.
He tells the newspaper he shot the scene with a body double and then grafted on Lohan's face in post-production.
The 2007 film flopped critically and commercially, making just $7 million (£4.4 million) at the box office.