COVENTRY City recorded their second consecutive goalless draw at the Ricoh Arena on Saturday afternoon to keep them 14th in the Championship table.
Academy debutant Ashley Cain had arguably the best chance to snatch the match with four minutes to go, his galloping run ending with a composed shot going just wide of goal.
But it was a tale of two halves at the Ricoh Arena as a first 45 minutes of relative inaction was followed up by a much more exciting second period.
Michael Doyle came closest to opening the scoring six minutes into the opening period.
But it was the only real effort on goal for the opening 45 minutes which was not ruled out by the linesman or the referee.
Osbourne produced a cross in the sixth minute following some good work from Kevin Thornton in the corner to get it to him, the delivery from Osbourne reminiscent of the delivery Aron Gunnarsson scored off last Tuesday night against Crystal Palace.
Doyle rose to meet the cross and directed his header just over Charlton 'keeper Rob Elliott's bar.
Elliott Ward then had his own aerial effort at goal two minutes later, meeting a deep corner from Danny Fox with his header cleared out of the goalmouth although the referee penalized him for a push.
Fox caused more problems for the Charlton back four a minute later, his left-sided cross just evading Clinton Morrison, Freddy Eastwood and Thornton, allowing Elliott to scramble the ball clear.
Addicks' Nicky Bailey tried his luck with a half-volley on 19 minutes, the effort flying a few feet over Keiren Westwood's bar.
Team mate Tresor Kandol also nearly put the visitors ahead two minutes later, Kelly Youga providing the cross for him to steer a low header past Westwood only for the linesman to disallow it for offside.
The second half started with a bit more passion, albeit misdirected, as Fox fought hard to win the ball off Lloyd Sam only for Sam to launch himself into the back of Fox's legs and spark a fracas before earning himself a booking.
Charlton came close to breaking the deadlock three minutes before the hour mark though, Zheng Zhi on the right cutting back a low cross for Shelvey who poked an effort goalward but had it deflected by Dann for a corner.
Eastwood found his shooting boots four minutes later, lashing a 30-yard effort just wide of Elliott's far post before slicing a half-volley wide from just inside the Charlton area while under the attention of two defenders.
Sky Blues Academy product Cain made his first senior appearance after 64 minutes and immediately brightened up the right flank, showing a clear desire to run at Addicks left back Youga.
And Doyle also saw his long-range effort almost take a fortunate deflection inside Elliott's near post on 68 minutes only for Elliott to push it wide.
Eastwood then came within a boot lace of grabbing the game's only goal with 20 minutes to go, Fox whipping in the resulting corner from Doyle's effort and Eastwood sticking a leg out only to steer the ball just wide of the post.
Cain had his first career effort on goal three minutes later, released by Osbourne and beating Darren Ward for pace although his shot was stopped by the legs of Elliott.
Mark Hudson headed a Nicky Bailey corner straight at Westwood with ten minutes to go, proving no trouble for the Coventry 'keeper.
But it was four minutes from time the Sky Blues had their best chance to snatch all the points and send Charlton into League One, Eastwood releasing Cain who sprinted towards goal and beat Youga but slid his composed finish past Elliott and inches wide of his far post.
Bailey struck the woodwork at the opposite end a minute later for Charlton, causing a moment of slight panic for the Sky Blues' rearguard.
But Cain's toil on the right wing ensured the Sky Blues kept much of the ball in Charlton's half in the closing moments as he beat Youga to the goal line with a late cross, Fox's resulting corner seeing out the game.
Attendance: 16,127 (387 away)
Teams
Coventry City: Westwood, Dann, Hall, Fox, Ward, Beuzelin (Walker 74), Thornton (Cain 64), Doyle, Eastwood, Osbourne, Morrison
Subs: Marshall (GK), Turner, Grandison
Charlton Athletic: Elliott, Youga, Bailey, Zhi, Hudson, Shelvey (Ambrose 67), Ward, Sam (Dickson 75), Racon, Butterfield, Kandol (Burton 84)
Subs: Randolph (GK), Holland, Dickson, Burton
