Accrington Stanley were favoured by the pundits for an instant return to League Two, but they have shown they have more about them. Grant put Charlton ahead on 15 minutes, but the home side equalised through Clark on 78 minutes.
Charlton fans unfurled a big banner in the away end: 'EFL, not fit for purpose.'
Charlton opened the scoring after 15 minutes when Lewis Page raced down the left wing and played in a cross, finding the head of Karlan Grant. The forward's header hit the underside of the crossbar and bounced down with the assistant referee judging it had crossed the line.
Grant could have doubled Charlton's advantage with a shot from 22 yards which was narrowly wide while Billy Kee came close for Stanley after 44 minutes but his header was just the wrong side of the upright.
Stanley pressed for the equaliser after the break but Charlton were dangerous on the breakaway, with Darren Pratley forcing a good save out of Middlesbrough loan keeper Connor Ripley.
The home side's pressure finally told when Sam Finley's ball caused chaos in the area and both Sean McConville and Offrande Zanzala had shots before Clark fired home from close range to secure a point.
Charlton are now 12th in the table.
Report from the News Shopper here: Forced to settle for point
The report from Louis Mendez of the SLP is here: Addicks settle for point
Lee Bowyer was not happy with the team's performance and warned 'they have to be better than they were today otherwise they’ll get thumped (on Tuesday against Peterborough)'. The shell shocked supremo slammed his side's decision making, saying 'We weren't good enough': Unacceptable draw