Fettis had little to do in the first half but following the break made three vital saves, including a one-handed reflex stop just after the Cherries equalised.
O'Driscoll believes that Fettis is a good signing by Law and was the difference maker.
"I thought Fettis was an astute signing for Nicky Law. The saves that he made stopped us winning the game," O'Driscoll said.