Championship leaders Coventry conceded more ground to the chasing pack as their festive hangover continued with a 1-1 draw against struggling Charlton.

Ellis Simms' early strike was cancelled out by Joe Rankin-Costello's second-half equaliser as the Sky Blues dropped two points.

It continued a mid-season dip which has now seen the early pacesetters take just nine points from 21 available in a run of seven matches since the start of December.

A draw allowed second-placed Ipswich to close the gap to eight points with a win over Oxford while Middlesbrough are a further point back after missing the chance to take advantage, losing at Derby.

For Charlton, a much-needed point saw them climb a place into 19th at the other end, four points clear of the relegation zone.

Coventry manager Frank Lampard can console himself and his stuttering team with the fact that 15 of the past 25 sides top of the second tier at Christmas went on to win the title.

That is something substantial to cling to.

Yet having established clear water between themselves and the rest with their free-scoring early season form, the sound of hooves closing will not help the nerves.

A draw against Charlton was probably a fair result, too.

Simms' third-minute goal, his ninth of the campaign, was a settler for the visitors after just two wins in six in December, the forward turning in a cross from the right flank from Milan van Ewijk from around 14 yards out.

But Charlton had their chances as well and had a big shout for a penalty turned down when Joel Latibeaudiere blocked a goalbound shot from Charlie Kelman after the half-hour mark.

The same defender also did less controversial work to deny Luke Berry, recovering to poke the ball back to his keeper when the Charlton man was about to shoot just before half-time.

Charlton came out the better side in the second half as well and for all that they needed goalkeeper Thomas Kaminski to pull off a double save from Haji Wright and Jamie Allen three minutes after the restart, on 69 minutes they pulled themselves level.

Strong work from Kelman saw the left-sided forward latch on to a through pass from inside his own half and outmuscle Miguel Angel Brau. His shot across goal was parried by Carl Rushworth into the path of Rankin-Costello, who finished high into the net from eight yards.

Coventry nearly snatched the lead back three minutes later, Liam Kitching spinning and poking a shot goalwards as Charlton struggled to clear but Kaminski once again pulled off an excellent save low to his left to turn it around the post.

For Charlton, a point was satisfying and a step in the right direction against a side who most will believe still look bound for the top tier.

But it remains just one win and only five points from their past 10 matches for Nathan Jones's side, form which will not banish thoughts that the Addicks could be travelling in the opposite direction in May.

Charlton manager Nathan Jones speaking to BBC Radio London:

"It was an excellent football game with both sides going right at the game to try and win it. To concede after two minutes and to put in the performance showed we have bags and bags of character.

"After the goal in the first half I thought we were brilliant. I thought we tested them, we were athletic. Second half they had one or two chances but we had so many situations. That was a top level Championship game.

"The level of performance we put in today… I'm proud. We have gone from a really tough time with injuries but when we have got our best players available that is the level of performance we can put in.

"I thought we were outstanding first half but people have told me we were better second half so I will have to watch it back."

On the penalty appeal: "His hand is down by his side but it hits his hand and stops it from going in the bottom corner. I don't know. I don't know the rules any more, I've got to be honest. When we have feedback there is always a way around everything."

Coventry boss Frank Lampard speaking to BBC CWR:

"Hard, tough and expected against a team who are in the image of their manager – a lot of passion, fight and direct.

"We get our early goal which was great and a lovely goal but it was hard to take control of the game on this pitch. We had the better chances and it was a mistake that led to their goal and without that we probably win the game.

"They had some moments of pressure but we are disappointed to take a point because that is where we are at. Sometimes you have to sit back and go 'ok, we are in a busy period where we are really stretched and trying to keep everyone fresh so we take our point'.

"We are not as clinical as we were earlier in the season but that was always going to come. I don't think any team in this league goes win, win, win and carries on like that."