Pompey failed to close the gap on the League One play-off places after being held to a draw by Morecambe.
John Mousinho's men had chances to secure victory at Fratton Park, with Tom Lowery twice firing narrowly past the post before the break.
Their best chance came right at the death, when Reeco Hackett met a Denver Hume cross and saw his header brilliantly saved by Connor Ripley.