A last-gasp own goal from Leeds United defender Andy O'Brien gifted Portsmouth a 3-3 draw at Elland Road.
The centre-back turned Nadir Ciftci's cross into his own net in injury-time as Pompey fought back from 3-1 down to claim a point.
Leeds took seven minutes to open the scoring through Gradel's close-range finish, and Jonathan Howson added a second three minutes later after running through Portsmouth's defence.
Billy Paynter could have added a third but Pompey replied on 33 minutes when David Nugent fired a shot into the top corner of Kasper Schmeichel's net.
Bradley Johnson looked to have settled the game with a 62nd-minute volley but Richard Hughes replied immediately to set up a tense finish and O'Brien's error completed their fightback.