New Nottingham Forest boss Steve Cotterill watched from the stands as his side slumped into the bottom two.
Lukas Jutkiewicz headed the only goal of the game in the 57th minute, just moments after Lee Camp made a brilliant save to deny Richard Keogh.
The well-taken goal secured Coventry only their second win of the season.
But their celebrations were muted after goalkeeper Joe Murphy was carried off on a stretcher following lengthy treatment.
Coventry boss Andy Thorn earlier confirmed his commitment to City after "unfounded and malicious" rumours he was set to quit and join Forest.
But he would have been less than impressed with his side's shaky start.
The Sky Blues threatened for the first time just before the half-hour mark as Clive Platt's looping header forced Camp to tip over the crossbar.
The second half continued to be a lacklustre affair until it suddenly burst into life after 10 minutes.
Forest's players felt the ball had crossed the touchline for a throw-in before Wes Morgan was forced to concede a corner. From the resulting set-piece, Camp produced a stunning save to keep out Keogh's header.
But Camp was powerless as another ball quickly came back into the area and Jutkiewicz was left unmarked to head home.
- Steve Cotterill left Portsmouth to take the reins at Nottingham Forest on Friday but assistant manager Rob Kelly was in charge for this game. He was unable to prevent a sixth defeat in seven league matches for Forest.
Clint Hill then headed Conor Thomas's effort off the line before Camp parried Bell's strike to safety.
With 20 minutes remaining, City goalkeeper Murphy collided in the air with Ishmael Miller and, after receiving lengthy treatment, was carried off to be replaced by Chris Dunn.
Forest substitute Robbie Findley nodded a good chance over from close range before Jutkiewicz headed on to the top of crossbar.
Despite 10 minutes of injury time because of the injury to Murphy, Forest were unable to find an equaliser.
Live Text Commentary
Full Time The match has reached full-time.90:00 +9:35
The referee blows for offside. Indirect free kick taken by Chris Dunn.90:00 +8:33
The ball is delivered by Andy Reid, Nathan Cameron manages to make a clearance.90:00 +7:05
Free kick awarded for an unfair challenge on Lukas Jutkiewicz by Wes Morgan. Chris Dunn restarts play with the free kick.90:00 +5:51
Shot from just outside the area by Robbie Findley misses to the right of the target.90:00 +4:17
The ball is crossed by Andy Reid, Headed effort from deep inside the penalty area by Chris Gunter misses to the right of the target.90:00 +3:58
Chris Gunter delivers the ball.90:00 +1:43 Substitution
Substitution Andy Reid on for Marcus Tudgay.90:00 +0:57
Inswinging corner taken by Sammy Clingan from the left by-line.89:32
Free kick awarded for an unfair challenge on Richard Keogh by Ishmael Miller. Chris Dunn takes the free kick.88:12
Nathan Cameron gives away a free kick for an unfair challenge on Radoslaw Majewski. The free kick is swung in right-footed by Lewis McGugan.88:06
The ball is sent over by Chris Gunter.82:34 Substitution
Substitution Conor Thomas goes off and Gael Bigirimana comes on.81:21
Radoslaw Majewski sends in a cross, Chris Hussey makes a clearance. Lewis McGugan takes a outswinging corner.80:54
Gary Deegan gives away a free kick for an unfair challenge on Chris Gunter. Lewis McGugan takes the free kick.80:20
Sammy Clingan delivers the ball, Lukas Jutkiewicz takes a shot.78:21 Substitution
Substitution Richard Wood goes off and Nathan Cameron comes on.77:12
The ball is crossed by Lewis McGugan, Robbie Findley produces a header from deep inside the six-yard box which goes wide of the right-hand post.76:45
The ball is sent over by Wes Morgan, blocked by Chris Hussey. Corner taken by Lewis McGugan.76:01
Inswinging corner taken by Lewis McGugan from the left by-line played to the near post, Richard Keogh manages to make a clearance.
Substitution Jonathan Greening goes off and Radoslaw Majewski comes on.75:11 Substitution
Substitution Robbie Findley joins the action as a substitute, replacing Matt Derbyshire.74:34 Substitution
Substitution Chris Dunn is brought on as a substitute for Joe Murphy.68:42
The ball is sent over by Chris Gunter.67:09
David Bell takes a shot. Fantastic save by Lee Camp.66:14
Richard Wood takes a shot. Clearance made by Jonathan Greening.65:38
Inswinging corner taken by Sammy Clingan from the left by-line.65:07
Lewis McGugan takes a shot. Save by Joe Murphy.64:10
Sammy Clingan takes the direct free kick.64:10 Booking
Booking Ishmael Miller is cautioned.63:53
Unfair challenge on Clive Platt by Luke Chambers results in a free kick.61:08
The ball is swung over by Chris Gunter, clearance by Richard Wood.59:34
Corner from right by-line taken by Sammy Clingan.58:56
Gary Deegan crosses the ball, Effort from 18 yards by Conor Thomas. Clearance made by Clint Hill.56:13
The assist for the goal came from Cyrus Christie.56:13 Goal scored
Goal! - Lukas Jutkiewicz - Coventry 1 - 0 Nott'm For Lukas Jutkiewicz finds the net with a headed goal from deep inside the penalty area. Coventry 1-0 Nottm Forest.55:32
The ball is swung over by Chris Hussey, Richard Keogh takes a shot. Save by Lee Camp. Cyrus Christie produces a cross,54:55
The ball is delivered by Lukas Jutkiewicz, Wes Morgan gets a block in. Corner from the left by-line taken by Sammy Clingan, save made by Lee Camp.51:49
Cyrus Christie produces a cross.51:12
Shot on goal by David Bell from inside the box goes harmlessly over the target.46:55
Ishmael Miller is ruled offside. Free kick taken by Joe Murphy.46:23
The ball is sent over by Chris Hussey, save made by Lee Camp.45:47
Lewis McGugan crosses the ball.45:01
The second half begins.45:00 +0:59 Half time
Half Time The referee blows for half time.45:00 +0:53
Centre by David Bell, Wes Morgan makes a clearance.43:01
Outswinging corner taken from the right by-line by Lewis McGugan.41:41
Corner taken by Sammy Clingan.40:08
Gary Deegan has shot on goal from just outside the area which goes wide of the right-hand upright.39:49
Sammy Clingan fouled by Marcus Tudgay, the ref awards a free kick. Free kick taken by Richard Wood.38:21
Ishmael Miller takes a shot. Blocked by Richard Keogh.37:37
Effort from inside the area by David Bell misses to the right of the goal.36:34
Guy Moussi challenges Sammy Clingan unfairly and gives away a free kick. Free kick taken by Joe Murphy.35:05
A cross is delivered by Chris Hussey, clearance by Wes Morgan. Corner taken by Sammy Clingan, Lukas Jutkiewicz has a headed effort at goal from deep inside the area missing to the right of the target.34:00
Centre by David Bell.32:59
Guy Moussi concedes a free kick for a foul on Gary Deegan. Direct free kick taken by Joe Murphy.32:23
David Bell challenges Matt Derbyshire unfairly and gives away a free kick. Lee Camp takes the free kick.31:47
Unfair challenge on Gary Deegan by Marcus Tudgay results in a free kick. Joe Murphy takes the free kick.30:45
Jonathan Greening fouled by David Bell, the ref awards a free kick. Free kick taken by Jonathan Greening.30:14
Matt Derbyshire concedes a free kick for a foul on Richard Keogh. Joe Murphy takes the direct free kick.27:21
Corner taken right-footed by Sammy Clingan.26:57
The ball is delivered by Cyrus Christie, Conor Thomas takes a shot. Save by Lee Camp.26:27
Free kick awarded for an unfair challenge on Guy Moussi by Clive Platt. Wes Morgan takes the free kick.25:25
Jonathan Greening concedes a free kick for a foul on Conor Thomas. Free kick taken by Sammy Clingan.22:41
Chris Hussey delivers the ball, save made by Lee Camp.19:53
The assistant referee flags for offside against Marcus Tudgay. Free kick taken by Joe Murphy.18:52
The ball is delivered by Chris Hussey, Wes Morgan makes a clearance.17:49
Chris Hussey delivers the ball, clearance by Wes Morgan.17:17
The offside flag is raised against Matt Derbyshire. Free kick taken by Joe Murphy.16:40
Ishmael Miller takes a shot. Joe Murphy makes a brilliant save.15:46
A cross is delivered by Ishmael Miller, Richard Wood gets a block in. Inswinging corner taken right-footed by Lewis McGugan, save made by Joe Murphy.15:18
Unfair challenge on Richard Wood by Ishmael Miller results in a free kick. Direct free kick taken by Sammy Clingan.13:27
Ishmael Miller takes a shot. Sammy Clingan gets a block in. Inswinging corner taken by Lewis McGugan from the left by-line, Headed effort from deep inside the area by Luke Chambers misses to the right of the goal.13:14
Guy Moussi sends in a cross, clearance by Richard Wood.11:35
Jonathan Greening delivers the ball, clearance made by Richard Keogh.10:30
The ball is sent over by Chris Gunter.8:59
Unfair challenge on Lukas Jutkiewicz by Clint Hill results in a free kick. Sammy Clingan crosses the ball in from the free kick, clearance by Wes Morgan.4:41
Ishmael Miller is flagged offside by the assistant referee. Joe Murphy restarts play with the free kick.4:07
Marcus Tudgay takes a shot. Save made by Joe Murphy.3:32
Ishmael Miller sends in a cross.3:19
Clint Hill crosses the ball.2:01
Ishmael Miller is caught offside. Free kick taken by Richard Wood.0:00
The referee gets the match started.
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