Forest's convincing 4-2 win over Leeds United on Boxing Day only added to the mystery surrounding the board's decision to sack O'Driscoll that evening, although a club statement seemed to indicate that their inconsistencies over the season had cost the former Doncaster and Crawley boss his job.
Nevertheless, the show must go on and McLeish will take charge of his first game against Crystal Palace on Saturday, who themselves are looking to get back into the top two after being beaten by leaders Cardiff on Wednesday.
|WEEKEND FIXTURES IN FULL
|Sheff W (12.30)
"The fact that a club of Forest's magnitude has offered me a job excites me greatly – it's a wonderful opportunity.
"I can't wait to get started and I'm looking forward to meeting the players, talking to them and taking my first training session."
Another managerial casualty in the league following Boxing Day saw Henning Berg sacked, after just 57 days in charge of Blackburn.
The former Rovers defender won just one of the 10 games he took charge of the team, taking them from fifth to 17th in the table in the process.
Goal.com understands that the Ewood Park hierarchy have identified Roberto Di Matteo as a possible replacement for the Norwegian, but Eric Black will take charge for their meeting with Barnsley at the weekend.
The Tykes beat Millwall before Christmas to spark hopes of climbing out of the relegation zone, but Wednesday's 2-1 defeat to Birmingham, that featured a host of missed chances for Keith Hill's side including a missed penalty from Craig Davies, sees them second-from bottom and three points from safety.
At the other end of the table, Cardiff hope to maintain their five-point advantage at the top when they face Millwall.
The Bluebirds' 2-1 win over Crystal Palace saw them reach the 50-point barrier, just one game after the halfway mark in the season, and Malky Mackay has hailed the wealth of options available to him, as he aims to return Cardiff to the top flight for the first time since 1962.
"This year we have a very similar sized squad to last year but there is more strength in depth and players go in and out on performance," the Scot told reporters.
"It is about making sure you take your chances and grab it. They are a great group with a lack of ego there and that makes them work hard for each other whether on the pitch, the bench or the squad."
The Lions will have right-back Adam Smith available after his red card against Barnsley before Christmas was overturned, but Chris Wood signed off his loan spell in the clash with the Tykes and is now thought to be close to sealing a permanent move to Leicester.
Hull City are sitting in second place and looking to take advantage of any slip-ups from the Welsh side when they host Yorkshire rivals Leeds in one of two lunchtime kick-offs.
|PLAYERS TO WATCH
|Chris Wood's goals were pivotal in firing Millwall into the play-offs, but the Kiwi striker has now returned to West Brom following a loan spell at the New Den and the onus has switched to the Irishman to get his shooting boots on and maintain the Lions' lofty league position.|
|Peterborough have stormed off the bottom of the table with three consecutive wins, and the 22-year-old, who joined on loan from Dagenham & Redbridge in November, has scored in each of them. Gayle has scored six in seven games for the Posh, who recently secured a permanent £500,000 deal for the hot-shot.|
|The Southampton loanee joined Nottingham Forest in the summer to link up with his former manager at Doncaster, Sean O'Driscoll. The Irishman has been removed from his post at the City Ground, but the 26-year-old remains one of the league's most lethal forwards and has finally hit form for Forest with five goals in his last seven appearances.|
Steve Bruce's side have consistently been in the promotion chase all season, but the former defender has demanded a more ruthless edge from his side, after Wednesday's stalemate against Leicester.
He told reporters: "The big chances - we should be scoring. Anyone who has seen us over the past four or five months will know that's the frustration.
"In big games especially, you can't be expected to create eight or nine chances.
"It's gnawing away at us all. It's not just the goalscoring it's all round we've got to contribute. I hope it's not going to be our Achilles heel."
The Whites confirmed a permanent deal for winger Ryan Hall on Thursday, after making five appearances on loan from Southend since October.
The nippy winger caught the eye when scoring four times in a developmental game for Neil Warnock's side, and the 64-year-old believes he has sealed a star of the future.
Warnock told Leeds' official website: "When we brought Ryan in I said 'I believe he is a player with potential for a big future.'
"I'm sure during the length of his contract Ryan will have the opportunity to establish himself at this level, and you can see that from his contribution at Huddersfield a few weeks ago.
"It's not just experienced players we are looking for to add to the squad, and if we feel there are youngsters like him available at the right prices we will look to the future as well."
At the very bottom of the table, a resurgent Peterborough travel to newly-bottom Bristol City, hoping to extend their three-game winning streak.
Darren Ferguson's men have hit top gear over Christmas, beating table-toppers Cardiff and then coming out on top in a stunning 5-4 win over Bolton, before crushing Wolves 3-0 on Boxing Day.
Now this consistency has to remain for us to get out of trouble. To win one game at this level is hard enough. To win three is fantastic.
After the game at Molineux, Ferguson told reporters: "It was a very good team performance. I played here at Wolves for five years and I know what the place is like, not many teams come here and win 3-0. It was a very good day.
"But I don't want us to stop there. We have to maintain the consistency right to the end of the season. If we perform to the levels I know we can then we can win games."
Derek McInnes' side slumped to the foot of the table after their Boxing Day clash with Watford was postponed due to a waterlogged pitch and long-serving midfielder Cole Skuse is eager to get back to action as soon as possible.
"We are raring to go after yesterday's postponement," he told the Robins' official website.
"We were all prepared and there was a big crowd expected but I think to call the game off was the right decision.
"With Peterborough also in the relegation zone the game has added significance. We have got to start picking up points at home.
"Obviously we had one eye on the teams around us who were playing [on Boxing Day] but we can't let other results affect our preparation for the game.
"We played well against Ipswich [1-1 draw on Dec 22] and I think we deserved to win the game. We could have been three or four up but we have got to take our chances."
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