ST. LOUIS - The St. Louis Rams stayed in-house Thursday in hiring a new offensive co-ordinator to replace Brian Schottenheimer, promoting quarterbacks coach Frank Cignetti to help turn around the long-struggling offence.

Schottenheimer left in January to become offensive co-ordinator at the University of Georgia. Cignetti will call plays, the team said. The Rams also announced the promotion of tight ends coach Rob Boras to assistant head coach/offence.

Cignetti, 49, has been with the Rams for three seasons. Before that he was offensive co-ordinator for several college programs, most recently Rutgers, in 2011.

"He's done a great job in some difficult circumstances and he brings a great body of work as a play caller at some significant college programs," coach Jeff Fisher said.

Cignetti helped Rams quarterback Sam Bradford to career highs in passing yards, touchdown passes and quarterback rating in 2012, and Bradford was on pace for an even better season in 2013 before injuring his knee seven games in and missing the rest of the year. He re-injured the knee in the 2014 preseason and missed the entire season.

The Rams' offence struggled without Bradford in 2014, finishing 6-10 and last place in the NFC West. Led by backup quarterback Shaun Hill and third-stringer Austin Davis, St. Louis ranked 28th in total offence and 21st in scoring.

Fisher said the expanded role for Boras "is sure to make us better as an offence."

Boras, 44, will help oversee all aspects of the offence but will particularly focus on the running game, Fisher said. He will continue as tight ends coach, a position he has held for the past three seasons.