Pompey made a flying start when Mahlon Romeo progressed forward with the ball before switching to Ronan Curtis who controlled the ball expertly on the edge of the box and fired an unstoppable dipping effort past, former Blues teammate, Craig MacGillivray.
Following the Republic of Ireland international’s strike, the Blues were very much in the ascendency and could have doubled their lead had John Marquis’ first touch not prevented him from firing towards goal after Marcus Harness had wriggled free of a challenge and slipped the ball into the strikers path.
Charlton were struggling to deal with Pompey’s press, and the game should have been out of sight in the 18th minute when Harness drove down to the touchline and squared the ball to Marquis, whose touch let him down once again, before he screwed the ball wide from inside the six-yard box.
Jonathan Leko was at the heart of all things good from the Addicks in the first half, and he tested the reflexes of Gavin Bazunu when he hit a hopeful effort towards goal from distance that the 19-year-old dealt with comfortably.
On the stroke of half-time the hosts almost drew level when Leko slipped the ball behind the Pompey defence, and into the path of Alex Gilbey, whose goal-bound effort was superbly directed wide by the feet of Bazunu.
Pompey’s early advantage was immediately cancelled out two minutes into the second half when Addicks substitute, Sean Clare, caught the visitors napping after a free-kick was taken shortly that allowed him latch onto the ball, before drilling home with his first touch of the match.
Charlton looked like a completely different outfit following the introduction of Clare, and he was at the centre of most of the Addicks’ attacks as he powered through midfield and teed up Elliot Lee, who saw his fierce effort well saved by Bazunu in the 55th minute.
The battle between Bazunu and Leko continued to progress in the second half as the former thwarted the ex-West Brom winger once again by tipping over his venomous strike from distance midway through the re-start.
Arguably against the run of the play, the Blues regained the lead with 20 minutes remaining when a slick passing move saw Marquis cutely backheel the ball into the path of Harness who made no mistake in dispatching it into the bottom corner from the centre of the box.
With Pompey looking to hold onto their narrow lead late on, Charlton grabbed themselves a point when Corey Blackett-Taylor drove down the left and squared the ball to Davison who tapped into an empty net from close range.