Bristol City have named Sean O'Driscoll as their new head coach on a 12-month rolling contract.
The former Nottingham Forest boss, 55, is believed to have turned down the vacant job at Blackpool in favour of joining the Championship's bottom club.
The Scotsman, 41, beat O'Driscoll to the role at Ashton Gate 15 months ago.
"The club has changed in a sense. In some ways they've come round to my way of thinking," O'Driscoll told BBC Radio Bristol.
"It's a good fit. Sometimes you have to go with your gut instincts and this just feels right.
"I like the way the club has been developed, but obviously not too happy about the league position.
"This has always been a well-respected club and that's not going to change. There's stability within the ownership and I think I can be successful here."
Former St Johnstone boss McInnes succeeded Keith Millen in October 2011, with the club bottom of the table and, although he saved them from relegation last season, they have managed only six wins from 26 games this term.
They are also the only team in the Football League who have failed to keep a clean sheet so far this season.
The club have confirmed McInnes' assistant, Tony Docherty, has also left the club.
O'Driscoll was sacked by Forest on Boxing Day after five months in charge, despite collecting 36 points from 24 games.
The former Republic of Ireland international started his managerial career with Bournemouth, where he was in charge between 2000 and 2006.
He then spent five years with Doncaster but was sacked in September 2011 after his side won just a single point from their first seven games.
O'Driscoll joined Forest as a coach under then manager Steve Cotterill during the 2011-12 campaign but left in the summer to take over at Crawley.
But he failed to take charge of a competitive game at the League One club after being coaxed back to the City Ground as manager following Cotterill's departure.
After his surprise sacking over Christmas, O'Driscoll entered talks over a move to Barnsley, who were then bottom of the Championship at the time, but he turned down the role.